How does propranolol make you feel

Propranolol: medicine for heart problems, anxiety and migraine

1. About propranolol

Propranolol belongs to a group of medicines called beta blockers. It's used to treat heart problems, help with anxiety and prevent migraines.

If you have a heart problem, you can take propranolol to:

  • treat high blood pressure
  • treat conditions that cause an irregular heartbeat (arrhythmia), like atrial fibrillation
  • help prevent future heart disease, heart attacks and strokes
  • help prevent chest pain caused by angina

Propranolol can help reduce your symptoms if you have too much thyroid hormone in your body (thyrotoxicosis). You'll usually take it together with medicines to treat an overactive thyroid.

This medicine is only available on prescription. It comes as tablets, slow release capsules, or as a liquid that you swallow.

2. Key facts

  • Propranolol slows down your heart rate and makes it easier for your heart to pump blood around your body.
  • It's usually prescribed for high blood pressure and other heart problems, but it can also help with the physical signs of anxiety, like sweating and shaking.
  • Your very first dose of propranolol may make you feel dizzy, so take it at bedtime. After that, if you do not feel dizzy, you can take it in the morning.
  • The main side effects of propranolol are feeling dizzy or tired, cold hands or feet, difficulties sleeping and nightmares. These side effects are usually mild and short-lived.

3. Who can and cannot take propranolol

Most adults and children aged 12 and over can take propranolol. But it is not officially approved for treating high blood pressure in children under 12 years old.

Propranolol is not suitable for everyone. To make sure it's safe for you, tell your doctor before starting to take propranolol if you:

  • have ever had an allergic reaction to propranolol or any other medicine
  • have low blood pressure or a slow heart rate
  • have heart failure which is getting worse
  • have diabetes
  • have liver or kidney problems
  • have severe blood circulation problems in your limbs (such as Raynaud's phenomenon), which may make your fingers and toes tingle or turn paler than usual or blue
  • have metabolic acidosis, when there is too much acid in your blood
  • have lung disease or asthma
  • are pregnant, trying to get pregnant or breastfeeding


How and when to take propranolol

Propranolol comes as 2 different types of medicine:

  • standard release – this releases propranolol into your body quickly, so you may need to take it several times a day depending on your dose
  • slow release – this releases the medicine slowly so you do not have to take it as often, once a day is usually enough

If you are taking it once a day, your doctor may advise you to take your first dose before bedtime, because it can make you feel dizzy. After the first dose, if you do not feel dizzy, take propranolol in the morning.

Important: Important

Keep taking propranolol even if you feel well. You will still be getting the benefits of the medicine.

Dosage and strength

Propranolol tablets come in strengths of 10mg, 40mg, 80mg or 160mg. The slow release capsules are 80mg or 160mg. The liquid comes in strengths of 5mg, 10mg, 40mg or 50mg in 5ml.

How much you take depends on why you need propranolol.

The usual doses for adults are:

  • high blood pressure – the starting dose is usually 80mg, taken twice a day. If this dose is not working well enough to reduce your blood pressure, your doctor may increase it to a maximum of 160mg twice a day
  • migraine or angina (chest pain) – 40mg, taken 2 or 3 times a day. This can be increased to 120mg to 240mg a day. Your doctor or pharmacist will explain how to split the dose over the day
  • irregular heartbeat (arrhythmia) – 10mg to 40mg, taken 3 or 4 times a day
  • anxiety – 40mg taken once a day which can be increased to 40mg taken 3 times a day
  • too much thyroid hormone (thyrotoxicosis) – 10mg to 40mg, taken 3 or 4 times a day

Doses are usually lower for people aged over 65 or people with a kidney or liver problem.

If your child needs propranolol, your doctor will usually use your child's weight to work out the right dose.

How to take it

Propranolol does not usually upset your stomach so you can take it with or without food. It's best to do the same each day.

Swallow the tablets whole with a drink of water. If you find the tablets difficult to swallow, some brands have a score line to help you break the tablet in half. Check the information leaflet for your brand to see if you can do this.

If you're taking capsules, swallow them whole with a drink of water. Do not break, chew or crush them.

If you're taking propranolol as a liquid, it will come with a plastic syringe or spoon to help you measure out the right dose. If you do not have one, ask your pharmacist for one. Do not use a kitchen teaspoon as it will not measure the right amount of medicine.

If you forget to take it

If you forget to take a dose of propranolol, take it as soon as you remember, unless it's nearly time for your next dose. In this case, just leave out the missed dose and take your next dose at the usual time.

Never take 2 doses at the same time. Never take an extra dose to make up for a forgotten one.

If you often forget doses, it may help to set an alarm to remind you. You could also ask your pharmacist for advice on other ways to help you remember to take your medicine.

If you take too much

An overdose of propranolol can slow down your heart rate and make it difficult to breathe. It can also cause dizziness and trembling.

The amount of propranolol that can lead to an overdose varies from person to person.

Urgent advice: Contact 111 for advice now if:

  • you take more than your prescribed dose of propranolol

Call 111 or go to 111 online

If you need to go to A&E, do not drive yourself. Get someone else to drive you or call for an ambulance.

Take the propranolol packet or leaflet inside it plus any remaining medicine with you.

5. Side effects

Like all medicines, propranolol can cause side effects in some people, but many people have no side effects or only minor ones.

Side effects often improve as your body gets used to the medicine.

Common side effects

These common side effects happen in more than 1 in 100 people. They're usually mild and short-lived.

Talk to your doctor or pharmacist if the side effects bother you or last more than a few days:

  • headaches
  • feeling tired, dizzy or weak
  • cold fingers or toes
  • feeling or being sick (nausea or vomiting), or diarrhoea
  • stomach pain

Serious side effects

It happens rarely, but some people have serious side effects when taking propranolol.

Tell a doctor or contact 111 straight away if:

  • the whites of your eyes turn yellow, your skin turns yellow although this may be less obvious on brown on black skin, or you have pale poo or dark pee – these can be signs of liver problems
  • you get nosebleeds that last for more than 10 minutes, unexplained bruising, or you bruise more easily than usual – these can be signs of low numbers of platelets in your blood (thrombocytopenia)

Go to or call 111.

Immediate action required: Call 999 or go to A&E now if:

  • you have shortness of breath with a cough which gets worse when you exercise (like walking up stairs), swollen ankles or legs, chest pain, or an irregular heartbeat – these are signs of heart problems
  • you have shortness of breath, wheezing and tightening of your chest – these can be signs of lung problems
Serious allergic reaction

In rare cases, propranolol may cause a serious allergic reaction (anaphylaxis).

Immediate action required: Call 999 or go to A&E now if:

  • you get a skin rash that may include itchy, red, swollen, blistered or peeling skin
  • you're wheezing
  • you get tightness in the chest or throat
  • you have trouble breathing or talking
  • your mouth, face, lips, tongue or throat start swelling

You could be having a serious allergic reaction and may need immediate treatment in hospital.

These are not all the side effects of propranolol. For a full list, see the leaflet inside your medicine packet.


You can report any suspected side effect using the Yellow Card safety scheme.

Visit Yellow Card for further information.

6. How to cope with side effects of propranolol

What to do about:

  • headaches – make sure you rest and drink plenty of fluids. Try not to drink too much alcohol. Ask your pharmacist to recommend a painkiller. Talk to your doctor if the headaches last longer than a week or are severe.
  • feeling tired, dizzy or weak – as your body gets used to propranolol, these side effects should wear off. If propranolol makes you feel dizzy, sit or lie down until you feel better. It's best not to drink alcohol as it will make you feel worse. Do not drive or ride a bike until you feel better.
  • cold fingers or toes – put your hands or feet under warm running water, massage them and wiggle your fingers and toes. Do not smoke or have drinks with caffeine in, as this can make your blood vessels narrower and further restrict blood flow to your hands and feet. Try wearing mittens (they're warmer than gloves) and warm socks. Do not wear tight watches or bracelets.
  • feeling or being sick or diarrhoea – stick to simple meals and do not eat rich or spicy food. It might help to take your propranolol after a meal or snack. Drink lots of fluids, such as water or squash, to avoid dehydration. Take small, frequent sips if you're being sick. Signs of dehydration include peeing less than usual or having dark, strong-smelling pee. Do not take any other medicines to treat diarrhoea and vomiting without speaking to a pharmacist or doctor. If you take contraceptive pills and you're being sick or have severe diarrhoea, your contraception may not protect you from pregnancy. Check the pill packet for advice.
  • stomach pain – try to rest and relax. It can help to eat and drink slowly and have smaller and more frequent meals. Putting a heat pad or covered hot water bottle on your tummy may also help. If you are in a lot of pain, speak to your pharmacist or doctor.

7. Pregnancy and breastfeeding

Propranolol and pregnancy

Propranolol is not thought to be harmful during pregnancy, but it may affect your baby's growth in later pregnancy. Discuss taking propranolol with your doctor or midwife as you may need extra scans to check your baby's growth.

If you're trying to get pregnant or you're already pregnant, talk to your doctor about the benefits and possible harms of taking propranolol. There may be other medicines that are better to use during pregnancy.

Propranolol and breastfeeding

If your doctor or health visitor says that your baby is healthy, it's OK to take propranolol while breastfeeding.

Propranolol passes into breast milk in tiny amounts. It has not been known to cause any side effects in breastfed babies.

It's important to treat your high blood pressure to keep you well. Breastfeeding will also benefit both you and your baby.

If you notice that your baby is not feeding as well as usual, or seems unusually sleepy, or if you have any other concerns about your baby, then talk to your doctor or health visitor.

Non-urgent advice: Tell your doctor if you're:

  • trying to get pregnant
  • pregnant
  • breastfeeding

For more information about how propranolol can affect you and your baby during pregnancy, visit the Best Use of Medicines in Pregnancy (BUMPS) website.

8. Cautions with other medicines

There are some medicines that may affect the way propranolol works.

Tell your doctor if you're taking:

  • other medicines for high blood pressure. The combination with propranolol can sometimes lower your blood pressure too much. This may make you feel dizzy or faint. If this keeps happening to you, your doctor may change your dose
  • other medicines for an irregular heartbeat such as amiodarone or flecainide
  • other medicines which can lower your blood pressure. These include some antidepressants, nitrates (for chest pain), baclofen (a muscle relaxant), medicines for an enlarged prostate gland like tamsulosin, or Parkinson's disease medicines such as levodopa
  • asthma or chronic obstructive pulmonary disease (COPD) medicines
  • diabetes medicines, particularly insulin – propranolol may make it more difficult to recognise the warning signs of low blood sugar. Speak to your doctor if you have low blood sugar levels without getting any of the usual warning signs. Check your blood sugar after exercise, and follow usual advice about checking it before driving, cycling or operating machinery
  • medicines to treat nose or sinus congestion, or other cold remedies (including those you can buy in the pharmacy)
  • medicines for allergies, such as ephedrine, noradrenaline or adrenaline
  • non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, diclofenac or naproxen. These medicines may increase your blood pressure, so it's best to keep them to a minimum

Mixing propranolol with herbal remedies or supplements

There's very little information about taking herbal remedies and supplements with propranolol. They are not tested in the same way as pharmacy and prescription medicines.

Medicine safety

Tell your doctor or pharmacist if you're taking any other medicines, including herbal medicines, vitamins or supplements.

9. Common questions about propranolol

How does propranolol work?

Propranolol is a type of medicine called a beta blocker.

Like other beta blockers, propranolol works by changing the way your body responds to some nerve impulses, including in the heart. It slows down your heart rate and makes it easier for your heart to pump blood around your body.

It works differently if you're using it for anxiety. When you are anxious, your brain makes chemical messengers called adrenaline and noradrenaline. These make your heart rate faster and make you sweat or shake. Propranolol helps block the effects of these chemical messengers. This reduces the physical signs of anxiety.

It's not fully understood how propranolol prevents migraines. It may work by relaxing the blood vessels involved, or by reducing activity in the visual cortex. This is the part of the brain where migraines are believed to start.

How long does propranolol take to work?

Propranolol usually starts to work in a few hours.

For heart conditions or high blood pressure, propranolol can take up to a week to reach its full effect. You may not feel any different but that does not mean it is not working. It's important to keep taking your medicine.

For migraines, it can take several weeks for propranolol to start making a real difference, so keep taking it.

How long will I take it for?

This depends on why you're taking propranolol.

For heart conditions or high blood pressure, treatment is usually long term and may be for the rest of your life.

For anxiety, you'll usually take propranolol for a short amount of time, to help with your physical symptoms. Speak to your doctor about the risks and benefits of taking it for more than a few months. This will depend on your symptoms, whether it's a one-off or a recurring problem, how well propranolol works for you and whether you get side effects.

For migraines, treatment can last for several months or years, depending on how bad your symptoms are.

Can I take propranolol for a long time?

Propranolol is generally safe to take for a long time.

If you're taking it for a heart condition, or to prevent migraines, it works best when you take it long term.

If you're taking it for anxiety, there do not seem to be any lasting harmful effects if you take it for several months or years. But it's best to take propranolol only for as long as you need it.

You'll need to have your blood pressure checked regularly if you're taking propranolol for a long time for migraines or anxiety.

What will happen if I stop taking it?

Talk to your doctor if you want to stop taking propranolol. If you're bothered by side effects, your doctor may be able to prescribe a different medicine instead.

Stopping propranolol suddenly may make your health problem worse. In addition, if you stop suddenly after taking it for a long time, you may get extra side effects as a reaction to stopping it. These include an irregular heart rate, sweating and shaking.

If you stop taking propranolol, it will take about 1 to 2 days for it to be completely out of your body but the side effects can last for up to 1 week.

How does propranolol compare with other heart medicines?

Propranolol works as well as other beta blockers for reducing blood pressure. The main difference between propranolol and other beta blockers is that it does not just affect your heart. It can affect other parts of your body too, such as your lungs.

There are lots of other medicines to lower your blood pressure and treat chest pain. They work in a different way to beta blockers and include:

  • ACE inhibitors like ramipril and lisinopril
  • angiotensin receptor blockers like candesartan
  • calcium channel blockers like amlodipine
  • medicines that make you pee more (diuretics) like furosemide

Beta blockers are not usually the first choice for high blood pressure. The medicine your doctor prescribes depends on your age and ethnicity.

If you're under 55 and not of African Caribbean or black African origin, you'll usually be offered an ACE inhibitor or an angiotensin receptor blocker.

If you're 55 or older, or you're any age and of African Caribbean or black African origin, you'll usually be offered a calcium channel blocker.

Sometimes you may have to try other blood pressure-lowering medicines if you get side effects. Many people need to take a combination of different medicines to lower their blood pressure.

How does it compare with other medicines for preventing migraine?

Atenolol, metoprolol, timolol and nadolol are all beta blockers and they work well in preventing migraines. However, most doctors prescribe propranolol.

There are some other medicines that are known to prevent migraines but they are not officially approved in the UK. They include amitriptyline, sodium valproate and gabapentin and they may have different side effects.

Topiramate can also be used to prevent migraines. It works just as well as propranolol. However, topiramate has not been officially approved for migraine for children under the age of 16.

Ask your doctor or pharmacist which medicine is best for you.

How does it compare with other medicines for anxiety?

Propranolol treats the physical symptoms of anxiety – for example, it stops your heart beating too fast. You'll usually only take propranolol for a short time.

The physical symptoms of anxiety are caused by chemical imbalances in the brain. Your doctor may prescribe an antidepressant like sertraline to treat these imbalances. You usually take antidepressants long term.

Many doctors prefer medicine-free treatments for anxiety. These include talking therapies like cognitive behavioural therapy. If you're having talking therapy, your doctor may prescribe propranolol at the same time. This will help you with your physical symptoms.

Will I need to stop taking propranolol before surgery?

Tell your doctor that you're taking propranolol if you're going to be put to sleep using general anaesthetic, or you're having any kind of major operation.

Your doctor may advise you to stop taking propranolol before surgery. This is because propranolol can lower your blood pressure too much when it's combined with some anaesthetics.

Can I drink alcohol with it?

Drinking alcohol can increase the blood pressure-lowering effect of propranolol, which can make you feel dizzy or lightheaded.

During the first few days of taking propranolol or after an increase in your dose, it's best to stop drinking alcohol until you see how the medicine affects you.

If you find propranolol makes you feel dizzy it's best to stop drinking alcohol.

Is there any food or drink I need to avoid?

Apart from being careful with alcohol, you can eat and drink normally while taking propranolol.

Eating a healthy, balanced diet can help if you have high blood pressure or another heart condition.

Will it make me put on weight?

Some people on propranolol say they put on weight, especially in the first few months of taking it. This is not known to be a common side effect of taking propranolol, and there is not enough information to say for sure why some people put on weight.

It could, for example, be because propranolol can make you feel tired which could make you less active. It could also affect the way your body uses energy.

If you're worried about putting on weight with propranolol, speak to your doctor.

Will it affect my contraception?

Propranolol will not stop your contraception working.

However, some types of hormonal methods of contraception, like the combined pill and contraceptive patch, are not usually recommended if you're taking propranolol or other medicines for high blood pressure. This is because some hormonal contraceptives can raise your blood pressure and stop propranolol working properly.

Talk to your doctor if you're taking a hormonal contraceptive.

If propranolol makes you sick (vomit) or have severe diarrhoea for more than 24 hours, your contraceptive pills may not protect you from pregnancy. Look on the pill packet to find out what to do.

Read more about what to do if you're on the pill and you're being sick or have diarrhoea.

Will it affect my fertility?

There is no evidence that propranolol affects fertility in men or women.

If you're trying to get pregnant, or you're having problems getting pregnant while on propranolol, speak to your doctor.

Will it affect my sex life?

Some people on propranolol say their sex drive goes down and some men find they cannot get an erection. However, this is not a common side effect and there is not enough evidence to say for sure that propranolol is causing it.

If you're having problems with your sex life, talk to your doctor.

Do I need to avoid playing sports?

You do not need to stop playing sports if you take propranolol. But do not push yourself too much.

Regular exercise is good for you because it lowers blood pressure by keeping your heart and blood vessels in good condition.

Be aware, though, that in some sports propranolol is not allowed if you're competing at a high level.

Can I drive or ride a bike?

Propranolol can make some people feel dizzy, especially when they first start taking it or after taking a bigger dose. If this happens to you, do not drive a car, ride a bike, or use tools or machinery.

It's an offence to drive a car if your ability to drive safely is affected. It's your responsibility to decide if it's safe to drive. If you're in any doubt, do not drive.

Talk to your doctor or pharmacist if you're unsure whether it's safe for you to drive while taking propranolol. GOV.UK has more information on the law on drugs and driving.

Can lifestyle changes help?

If you have heart problems, you can boost the health of your heart by making some key lifestyle changes. These changes will also help if you have high blood pressure.

  • Quit smoking – smoking increases your heart rate and blood pressure. Quitting smoking brings down your blood pressure and relieves heart failure symptoms. Try to avoid second-hand smoke too.
  • Cut down on alcohol – drinking alcohol while you're taking propranolol can make you feel dizzy or light headed. Also drinking too much alcohol raises blood pressure over time and makes heart failure worse. It's best to keep to the recommended limit of no more than 14 units of alcohol a week. A standard glass of wine (175ml) is 2 units. A pint of lager or beer is usually 2 to 3 units of alcohol.
  • Exercise – regular exercise lowers blood pressure by keeping your heart and blood vessels in good condition. It does not need to be too energetic, walking every day will help.
  • Eat well – aim to eat a diet that includes plenty of fruit and vegetables, wholegrains, fat-free or low-fat dairy products and lean proteins. It's a good idea to follow these tips for a lower salt diet too. Eating too much salt is the biggest cause of high blood pressure. The more salt you eat, the higher your blood pressure will be. Aim for no more than 6g of salt a day.
  • Deal with stress – when you're anxious or upset, your heart beats faster, you breathe more heavily and your blood pressure often goes up. This can make heart failure worse too. Find ways to reduce stress in your life. To give your heart a rest, try napping or putting your feet up when possible. Spend time with friends and family to be social and help avoid stress.

If you get severe headaches, there are steps you can take to help prevent migraines. This includes working out what things trigger an attack so you can avoid them.

What It's Like to Take Propranolol For Anxiety | Blog

Rachel explains what it was like to take propranolol to treat her anxiety a few months before sitting her A-Levels.

Everybody responds to medication differently. This blog only represents the author's experience. For more information, have a look at our medication pages. For medical advice, always speak to your doctor.

Exam stress

I first started taking propranolol for anxiety a few months before my A-Levels.

As a high-achieving student, I was predicted top grades across all my subjects. From February onwards I was up late every night rewriting my notes over and over again to ensure I didn’t miss the grades I needed to get onto my chosen course at uni.

As the exams drew closer, I started to experience obsessive negative thoughts about failing, along with images of me completely blanking in the exam, which made me very panicked and anxious. I started to lose weight and I stopped sleeping properly, which led to me doing worse than expected in mock exams, making me even more nervous.

As the exams drew closer, I started to experience obsessive negative thoughts about failing, along with images of me completely blanking in the exam, which made me very panicked and anxious.

Visiting my GP

I realised the negative cycle I was getting into and my mum and I went to see my GP, who prescribed me citalopram for depression and propranolol for anxiety. She prescribed me 10mg tablets of propranolol and told me I could take up to four tablets a day (so 40mg max) whenever I felt anxious.

She was very helpful in explaining to me that lots of young people experience anxiety around the time of their A-Levels. She even wrote a letter that my school could send to my exam boards asking them to take my mental health condition into account.

I noticed that my body seemed much less tense and calmer within just a few days of taking the propranolol and my heart rate seemed to slow down again. I was definitely still nervous by the time my exams came around but it was a kind of anxiety that I could cope with, not one which threatened to overwhelm me. I continued taking the medication (but at a lower dosage) right up until after my A-Level results were published, as it helped keep me calm in the lead–up to results day. However, I decided to come off it before I started university.

I was definitely still nervous by the time my exams came around but it was a kind of anxiety that I could cope with, not one which threatened to overwhelm me.

Effects and side effects

Propranolol has the beneficial effect of de-stressing my body and making me feel less tense and wound-up. Because I am still prescribed the 10mg tablets I can take them whenever I need them, which means I can get a hold on my anxiety wherever I am.

The only side effects I experienced are that sometimes it makes me feel a bit light-headed and I feel as if my concentration can suffer because of this. Also, because I suffer from low blood pressure, I have to make sure I spread out my propranolol tablets otherwise I might faint as they also lower your blood pressure. The tablets do seem to become less effective over time, as I think your body starts to get used to them, but they have been really useful in helping me manage my anxiety and get on with my life when I need to!

Because I suffer from low blood pressure, I have to make sure I spread out my propranolol tablets otherwise I might faint as they also lower your blood pressure.

Coming off propranolol

Coming off propranolol was surprisingly painless; I felt a bit tense at times, but other than that there were no nasty withdrawal effects.

I have been prescribed propranolol twice since then: once in my second year at university when I had a particularly severe episode of anxiety and depression which really affected my life, and again last October when my workplace ran into financial difficulties and stopped paying their staff before making us all redundant. Both times I took propranolol alongside antidepressants and both times it helped me cope with the physical feelings of anxiety. However, I would say it was most effective for me the first time I took it during my A-Levels.

More information and advice

We have tips and advice to help you find the support you need. Take a look at our guides.

Where to get help

However you're feeling, there are people who can help you if you are struggling. Here are some services that can support you.

Thanks for sharing your story Rachel

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Active ingredient PROPRANOLOL (PROPRANOLOLUM) | Compendium - drug reference book

  • Pharmacological properties
  • Indications PROPRANOLOL
  • Application of PROPRANOLOL
  • Contraindications
  • Side effects
  • Special instructions
  • Interactions
  • Overdose
  • Diagnosis
  • Recommended alternatives
  • Trade names

Medicines containing the active ingredient PROPRANOLOL

Prices in pharmacies

Prices in pharmacies

Prices in pharmacies

Prices in pharmacies

Propranolol is a lipophilic non-selective blocker of β-adrenergic receptors without ICA. Reduces heart rate and force of heart contractions, slows down AV conduction, reduces myocardial oxygen demand. It has a membrane-stabilizing effect and reduces the incidence of ectopic foci. The therapeutic effect consists in a negative chronotropic and inotropic effect on the myocardium. The hypotensive effect stabilizes by the end of the 2nd week of treatment.

Propranolol is resorbed in the digestive tract by more than 90% and during the initial passage through the liver is metabolized by almost 70%. Bioavailability - about 30%. With long-term use, propranolol is almost completely metabolized, and up to 18 different metabolites can be identified. 4-Hydroxypropranolol has a weak β-adrenolytic activity. The volume of distribution of propranolol is 3.61 l / kg of body weight, binding to plasma proteins is 93%. C max in plasma is achieved 1-2 hours after administration. Elimination of propranolol is carried out mainly through the liver and more than 90% in the form of metabolites. T ½ — 3–6 h.

AH, hyperkinetic heart syndrome, ischemic heart disease, tachyarrhythmias, migraine prophylaxis, essential tremor, symptomatic treatment of hyperthyroidism.

orally 10-15 minutes before meals, 10-20 mg 2-4 times a day. Doses are gradually increased to 40 mg 4-6 times a day.

decompensated heart failure (NYHA III and IV), cardiogenic shock, II-III degree AV block, bradycardia (<50 bpm), sinoauricular block, severe arterial hypotension, peripheral circulatory disorders, asthma, COPD, metabolic acidosis hypersensitivity to propranolol.

fatigue, dizziness, headache, paresthesia and feeling of coldness in the extremities, dyspepsia, bronchospasm, skin reactions, conjunctivitis, worsening signs of heart failure, bradycardia, AV conduction disturbances, arterial hypotension, sleep disturbances, depression, nightmares, hallucinations, increased peripheral circulatory disorders, decreased lacrimation, hypoglycemia, a feeling of dry mouth, cramps and muscle weakness, potency disorders, in some cases visual impairment and keratoconjunctivitis, increased angina attacks.

Patients with pheochromocytoma should be treated concomitantly with α-adrenergic blockers. Propranolol should be used with caution in AV conduction disorders, in patients with diabetes mellitus and during fasting. In case of impaired liver and kidney function, it is necessary to reduce the dose of propranolol.

Propranolol can affect the psychophysical abilities of the body, weakening attention and slowing down responses, especially with the simultaneous use of alcohol or drugs that depress the central nervous system.

Propranolol crosses the placental barrier. Studies on the use of propranolol in the first trimester of pregnancy have not been conducted. In order to prevent bradycardia, arterial hypotension, hypoglycemia, respiratory depression (neonatal asphyxia) in a newborn, it is necessary to interrupt propranolol therapy 48–72 hours before the expected date of delivery. The newborn should be left under medical supervision for 48-72 hours.

β-adrenergic blockers are contraindicated for intravenous therapy with calcium antagonists (verapamil and diltiazem) (with the exception of intensive care). With the simultaneous use of propranolol and norepinephrine or MAO inhibitors, a sharp increase in blood pressure is possible. When propranolol is combined with tricyclic antidepressants, barbiturates, anesthetics, antihypertensive and vasodilator drugs and diuretics, a sharp decrease in blood pressure is observed. The cardiodepressive effect of propranolol is potentiated by its combination with antiarrhythmic or anesthetic agents. The negative chronotropic and dromotropic effect of propranolol is manifested when it is combined with reserpine, clonidine, methyldopa, guanfacine and cardiac glycosides. Propranolol enhances the effects of tubocurarine. When taking propranolol and insulin or oral hypoglycemic drugs, the symptoms of hypoglycemia are masked, especially during exercise. Cimetidine increases the content of propranolol in the blood plasma.

The symptoms of propranolol intoxication depend on the initial state of the patient. In severe heart failure, even low doses of propranolol can cause signs of overdose, the symptoms of damage to the digestive tract, cardiovascular system and central nervous system predominate. There may be a feeling of fatigue, loss of consciousness, mydriasis, sometimes convulsions, arterial hypotension, bradycardia up to asystole, bronchospasm, hypoglycemia, shock.

To eliminate the symptoms of overdose, intravenous administration of 1–2 mg of atropine is indicated, as well as the use of drugs with β-sympathomimetic activity (dopamine, dobutamine, isoprenaline, orciprenaline, epinephrine). Glucagon should be administered initially in / in a dose of 0.2 mg / kg, then for 12 hours to bring the dose to 0.5 mg / kg.

Forget everything. Soon. Neurophysiologists seem to have taken the penultimate step towards targeted editing of memories

© Olga Skvortsova / Chrdk.

Sometimes things happen to us that we want to forget. Unfortunately, we are not allowed to control our memory - to erase memories at will, treating them like files on disk drives. But what if the memory is still subject to purposeful modification? While science fiction has explored the threats embodied in such power, science seems to be getting close to giving science fiction writers a chance to test their hypotheses against reality.

Our memories largely determine our personality. This is especially true for episodic memory - the one that stores memories of past years and preserves all the vicissitudes of your biography. It persistently reminds us of who we are and who we used to be. But here's the problem - we don't always want to be who we are. Almost everyone has moments in their biography that it would be nice to forget. Some adventures can even lead to the formation of post-traumatic stress disorder, often tormenting combat veterans and accident victims. Maybe they can be erased?

If you think that a diary or a notebook is a good metaphor for memory, then I hasten to upset you. Research shows that our memory is nothing like written text or videotape. It is rather a soft, dynamic structure of associations and feelings, which is also overwritten with each playback. Difficult? Well, what do you want! Not only is the brain itself the most difficult object to study - no joke, a system of almost 100 billion neurons with several trillion neural connections that controls the body and creates the inner world of consciousness. So this seemed not enough to evolution - it also put a real time machine there, allowing us to mentally return to the past and live it again.

In principle, if at the molecular and cellular level we already have a little idea of ​​the memory device, then it is already much more difficult to clearly say what it is on the scale of the whole brain. It is also difficult to give it a universal definition that would fit both the brain as a whole and each neuron individually. We can’t even really say where exactly memory “sits”: in a person, almost all the structures of the cerebral hemispheres are involved in remembering. So the targeted and complete removal of a particular memory seems hardly possible, even in the long run.

It is all the more impossible to imagine approaches that would allow us to be in the place of the heroes of “Eternal Sunshine of the Spotless Mind” by deleting memories of a specific person - this package of memories would include too complex a set of associations and emotions.

But to become like the hero of the TV series "Homecoming", who, upon returning from Iraq, was drugged to erase traumatic memories of the war and thus regain combat capability, apparently, it will soon become quite possible. The study, whose course is very reminiscent of a prequel to a five-hour story about the restless conscience of a psychologist by Julia Roberts, tells a recent publication in the scientific journal Science Advances .


Walter Kruse is taking the "forgetfulness pill". frame from Homecoming (2018) / Amazon Prime / Youtube

It is already clear that the hippocampus plays the most important, if not the key, role in the formation and reproduction of episodic memory. The classical view of this part of the brain suggests that, among other things, it is a temporary storage of memory - a kind of information hub, which is necessary both for the formation of a memory and for its reproduction. Damage to the hippocampus very often leads to impaired episodic memory. Especially indicative here is the example of Kent Cochrane, the famous patient of K.C., who lost both hippocampi at once and lost the ability to both remember the events of his life and recall the facts of his biography. It is curious that other types of memory, such as semantic, which includes knowledge about the facts and the structure of the world, remained with Kent practically untouched.

Well, cutting out the hippocampus of a victim of PTSD is a very bad idea, but maybe there is some way to pharmacologically influence it to prevent the memory from sticking, and ideally destroy it altogether? It turns out that today mankind knows several approaches to solving this problem.


Illustration from a 1918 anatomy textbook with the designation of the hippocampus. Henry Vandyke Carter (adapted by Looie496) / Wikimedia commons

Everyone knows that exciting, including truly terrible events, are very well remembered. The main culprit for this is the amygdala, this part of the brain is adjacent to the hippocampus. In a stressful, and therefore important situation for survival, her adrenoreceptors are activated under the influence of norepinephrine, and she herself makes the hippocampus record everything in great detail, with all emotional nuances and associations.

Therefore, as a safe way to reduce the severity of traumatic memories, blockers of β-adrenergic receptors, the very ones that cause the amygdala to respond to stress, have been proposed. It remained only to choose from this wide group of drugs such that it passed through the blood-brain barrier into the brain. As a result, the researchers stopped their choice on propranolol , widely known as a means to reduce pressure. Since the idea is to use the drug to prevent the formation of long-term, painful, emotionally charged memories of trauma, it is recommended to start taking it no later than six hours after experiencing the traumatic experience. At the same time, it must be recognized that over the 15-20 years of propranolol use for the prevention of post-traumatic disorder, a significant amount of information has accumulated on the effectiveness of such therapy. And she raises, well, oh, very big doubts.


3D model of the S-propranolol used in the first experiment. Vaccinationist / Wikimedia Commons / CC BY-SA 4.0

Another interesting, albeit still only potential, possibility has been identified by scientists looking at how long-term memory is formed. Long-term preservation of information in the brain requires the formation of new neural connections, or at least a qualitative change in the conductivity of existing ones. These processes require protein synthesis and take a significant amount of time - not even seconds, but minutes. Perhaps those who, like this author, have had the dubious pleasure of experiencing a concussion, also know the feeling of losing any memory of the last minutes before the injury. This local amnesia is precisely due to the fact that at first the memory lives only in the form of a specific pattern of neuronal activity, which disintegrates relatively easily under the influence of a fairly strong blow to the back of the head. Only minutes later, the memory of the event begins to “freeze” in the structure of connections between neurons. The formation of these bonds requires protein synthesis, so temporarily blocking it can easily prevent a memory from being fixed.

Works on animal models of post-traumatic stress disorder show that if after stress a rat received an injection of a protein synthesis blocker, anisomycin , then it did not subsequently develop pronounced stress behavior.

True, anisomycin cannot cross the blood-brain barrier (the line of demarcation between the blood and the brain) on its own, therefore it has to be delivered directly to the hippocampus by injecting the substance into this area of ​​the brain, and there can be no talk of any tablets with anisomycin.

Other, safer substances, such as valproic acid, clonazepam, and some cannabinoids, have a similar, although less pronounced effect on the consolidation of memories.

But even more exciting opportunities for us open up the peculiarities of replaying memories. Have you ever thought that the more often you turn to history from your own past, the more incredible details it acquires? This is partly because the retrieval of information from our memory is an active process, more like reconstruction than reading. The imagination is actively involved in it, and along the way, the brain often forms completely new associative connections, changing the memory. In the scientific tradition, this read-rewrite process is aptly called reconsolidation. The biochemical mechanism of this process has much in common with the primary fixation - consolidation - of a memory and, apparently, significantly destabilizes the original memory. Therefore, at the moment of re-experiencing the past, we, apparently, can introduce the same protein synthesis blocker - anisomycin - into the brain of the remembering all the same, and thus save the patient from an already fully developed post-traumatic disorder (although such procedures have so far been carried out only on rats) or even to alleviate his condition. But again, this method looks poorly applicable to humans: protein synthesis blockers are quite strong toxins. However, studies show that the already familiar beta-blocker propranolol, introduced at this moment, is able to reduce the emotional sharpness of the memory (as well as some psychological techniques, which we will not dwell on in more detail).

And now new, promising data on this, in general, not too studied topic, was brought by a very recent publication in the journal Science Advances . In it, the researchers used the already familiar method of destabilizing memories, using another pharmacological drug for this - the anesthetic propofol . In general, the scientists came up with the idea to use it when they observed patients undergoing electroconvulsive therapy - yes, that same electroshock treatment from the immortal One Flew Over the Cuckoo's Nest. Now this treatment, although it has ceased to be as popular as in the old days, is still sometimes used, for example, as in our case, for the treatment of unipolar depression.


Randle McMurphy before electroconvulsive therapy. One Flew Over the Cuckoo's Nest (1975) session, they remembered her much worse than those who did not remember her before the electric shock. But what does anesthetics have to do with it, you ask?

And despite the fact that in our philanthropic time, electroconvulsive therapy is carried out under general anesthesia, without medieval heartbreaking scenes that a reader familiar with the history of psychiatry could imagine. Scientists thought: maybe it was not the electric shock that caused such a noticeable effect, but the anesthetic etomidate , which was not noticed by anyone? And we decided to take a closer look at general anesthetics - substances that bind to the gamma-aminobutyric acid receptor and enhance the effect of its activation.

In this way, the scientists arrived at their latest study, in which they studied the effect of another similar anesthetic, propofol , on memory destabilization. Here they also showed maximum philanthropy and concern for patients. Knowing that anesthesia with propofol sometimes results in the death of patients, they decided to play it safe and experiment with those who were given propofol out of necessity. And no, these were not Missouri death row inmates. These were patients undergoing an unpleasant (and hopefully unfamiliar) endoscopy.

The protocol of the experiment largely repeated the previous work. Initial training with a story that provokes emotions, a pause of one week, and then a few questions about the history of a week ago - right in the endoscopy room before the introduction of anesthesia. A day after the procedure - another measurement of memory quality. It was he who showed that patients who had to remember the story right before anesthesia remembered it much worse than those who thought about something of their own before receiving propofol.

Thus, it was confirmed that anesthesia, and not the shock itself, is responsible at least partly for the "erasing" of destabilized memory during electroshock.

Even more interesting was the fact that the effect of propofol affected only the emotionally rich parts of the story, but practically did not affect the neutral ones.

However, it is still not entirely clear how a substance that enhances the activity of the gamma-aminobutyric acid receptor affects memory overwriting, especially selective, although these data are consistent with previous results obtained in animals. But the main thing is that it seems that we have become one step closer to the technique of directed removal of emotionally charged memories and one day we will be able to extract them from the memory of those who have experienced traumatic experiences, for example.

No, for now it is obvious that loading information into memory or completely deleting given memories will remain the professional field of Hollywood screenwriters, but not doctors. However, as we see, we have already learned how to selectively reduce the emotional sharpness and detail of memories with the help of a relatively harmless anesthetic.

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