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1. About lorazepam

Lorazepam belongs to a group of medicines called benzodiazepines.

It's used to treat anxiety and sleeping problems that are related to anxiety.

It can be taken to help you relax before an operation or other medical or dental treatment. This is known as a "pre-med".

Lorazepam is available on prescription only. It comes as tablets and as a liquid that you swallow.

It can also be given as an injection in hospital if you're having a seizure or fit.

It's also known by the brand name Ativan.

2. Key facts

  • Lorazepam tablets and liquid start to work in around 20 to 30 minutes. The full sedating effect lasts for around 6 to 8 hours.
  • The most common side effect is feeling sleepy (drowsy) during the daytime.
  • It's not recommended to use lorazepam for longer than 4 weeks.
  • If lorazepam makes you feel sleepy, do not drive, ride a bike or use tools or machinery.
  • Do not drink alcohol while taking lorazepam. It can make you sleep very deeply.

3. Who can and cannot take lorazepam

Lorazepam can be taken by adults and children aged 13 years and older for anxiety.

It can also be taken by adults and children aged 5 years or older as a "pre-med".

Lorazepam is not suitable for everyone.

To make sure it's safe for you, tell a doctor before starting lorazepam if you:

  • have had an allergic reaction to lorazepam or any other medicine in the past
  • have liver or kidney problems
  • have breathing or chest problems
  • have myasthenia gravis, a condition that causes muscle weakness
  • have sleep apnoea, a condition that causes breathing problems when you're asleep
  • have (or have had) depression or thoughts of harming yourself
  • have been diagnosed with personality disorder
  • have (or have had) problems with alcohol or drugs
  • have arteriosclerosis, a condition that affects blood flow
  • are trying to get pregnant, are already pregnant or breastfeeding
  • have glaucoma, a condition that causes high blood pressure in the eye
  • are going to have a general anaesthetic for an operation or dental treatment

4. How and when to take it

Always take lorazepam exactly as a doctor or pharmacist has told you.

Lorazepam tablets come as 0.5mg, 1mg and 2.5mg tablets. The liquid contains 1mg of lorazepam in each 1ml.

The usual dose for:

  • anxiety – 1mg to 4mg each day; your doctor will tell you how often you need to take it
  • sleep problems – 1mg to 2mg before bedtime (lorazepam will start to work in around 20 to 30 minutes)
  • a pre-med for adults – 2mg to 3mg the night before the procedure and then 2mg to 4mg about 1 to 2 hours before your procedure
  • a pre-med for children aged 1 month to 11 years – dose will depend on the child's weight
  • a pre-med for children aged 12 to 17 years and up – 1mg to 4mg the night before the procedure and/or at least 1 hour before the procedure

If you're older than 65 years or have liver or kidney problems, a doctor may recommend a lower dose.

Will my dose go up or down?

Lorazepam is usually prescribed for a short time, from a few days to 4 weeks. Your dose may go up or down until your doctor is happy you're on the right dose.

Your doctor may gradually reduce your dose at the end of the course of treatment before stopping completely.

What if I forget to take it?

If you forget to take your lorazepam:

  • for anxiety – if it's less than 3 hours since your missed dose, take it as soon as you remember. If more than 3 hours have passed, skip the missed dose.
  • for sleep problems – leave out the missed dose if you have not taken it by bedtime. Take you usual dose the next night.
  • before an operation or procedure (pre-med) – read any information you were given by the hospital about your procedure, which may have advice about missed doses. If it does not, call the hospital to ask what to do next.

If you forget to take lorazepam, never take a double dose to make up for a forgotten tablet.

What if I take too much?

Urgent advice: Contact 111 for advice if:

  • you take too much lorazepam

Go to or call 111

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 lorazepam packet or leaflet inside it, plus any remaining medicine, with you.

5. Side effects

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

Common side effects

These common side effects happen to more than 1 in 100 people.

If you get these side effects, keep taking the medicine and speak to a doctor:

  • feeling sleepy or very tired in the daytime
  • muscle weakness
  • problems with your coordination or controlling your movements

Serious side effects

It happens rarely in less than 1 in 1000 people, but some people have serious side effects when taking lorazepam.

Tell a doctor straightaway if:

  • your breathing becomes very slow or shallow
  • your skin or the whites of your eyes turn yellow; this could be a sign of liver problems
  • you find it difficult to remember things (amnesia)
  • you see or hear things that are not there (hallucinations)
  • you think things that are not true (delusions)
  • you keep falling over
  • you notice mood changes such as talking too much, feeling overexcited, restless, irritable or aggressive

Mood changes can become serious and are more likely in children or if you're over 65.

Serious allergic reaction

In rare cases, lorazepam 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 lorazepam. For a full list, see the leaflet inside your medicine packet.


You can report any suspected side effect to the UK safety scheme.

6. How to cope with side effects

What to do about:

  • feeling sleepy, or unusually tired in the daytime – do not drive, ride a bike or use tools or machinery until you feel better. Do not drink any alcohol as this will make you feel worse. This side effect should get better as your body gets used to the medicine. If your symptoms do not improve after a week or get worse, speak to a doctor as you may need a lower dose.
  • muscle weakness – if you get unusual muscle weakness, which is not from exercise or hard work, talk to a doctor. You may need a blood test to find the cause.
  • problems with your coordination or controlling your movements – if your symptoms do not improve after a week or get worse, speak to a doctor as you may need a lower dose.

7. Pregnancy and breastfeeding

There's not enough information to know if lorazepam is safe to use in pregnancy. It might mean your baby is born with withdrawal symptoms.

If you become pregnant while taking lorazepam, speak to a doctor.

Your doctor can explain the risks and the benefits of taking lorazepam and will help you choose the best treatment for you and your baby.

You may need to keep taking lorazepam during pregnancy as it's important for you to remain well.

Lorazepam and breastfeeding

If a doctor or health visitor says your baby is healthy, you can use lorazepam during breastfeeding. It's recommended that you only take a low dose occasionally or for a very short time.

Lorazepam passes into breast milk in small amounts.

If you're breastfeeding or want to breastfeed, talk to a doctor or pharmacist, as there might be better medicines for you. It will depend on what you're taking lorazepam for.

If you notice that your baby is not feeding as well as usual, seems unusually sleepy, has unusual breathing, or if you have any other concerns, talk to a health visitor or doctor as soon as possible.

Non-urgent advice: Talk to a doctor if you're:

  • trying to get pregnant
  • pregnant
  • breastfeeding

8. Cautions with other medicines

Some medicines interfere with the way lorazepam works and increase the chances of you having side effects.

Speak to a doctor or pharmacist before starting lorazepam if you take any of the following:

  • antidepressants and antipsychotics used to treat mental health problems
  • anticonvulsants used to treat epilepsy
  • hypnotics used to treat anxiety or sleep problems
  • drowsy or sedating antihistamines, such as chlorphenamine or promethazine
  • strong painkillers, such as codeine, methadone, morphine, oxycodone, pethidine or tramadol
  • HIV medicines, such as ritonavir, atazanavir, efavirenz or saquinavir
  • rifampicin, a medicine for bacterial infections or antifungal medicines, such as fluconazole
  • proton pump inhibitors (PPIs) – medicines for reducing stomach acid, such as omeprazole or esomeprazole
  • muscle relaxants, such as baclofen and tizanidine
  • disulfiram, a medicine for alcohol addiction
  • isoniazid, a medicine for tuberculosis
  • theophylline, a medicine for asthma and other breathing problems

Mixing lorazepam with herbal remedies or supplements

There's very little information about taking herbal remedies and supplements with lorazepam.

Do not take herbal medicines for anxiety or insomnia, such as valerian or passionflower, with lorazepam. They can increase the drowsy effects of lorazepam and may also have other side effects.


For safety, tell a doctor or pharmacist if you're taking any other medicines, including herbal medicines, vitamins or supplements.

9. Common questions

How does lorazepam work?

Lorazepam belongs to a group of medicines called benzodiazepines.

It works by increasing the levels of a calming chemical, gamma-amino-butyric-acid (GABA), in your brain.

Depending on your health condition, this can make you feel calmer, relieve anxiety or stop a seizure or fit.

How will it make me feel?

Lorazepam will help you feel calmer and it can help reduce your feelings of anxiety.

It can also make you feel sleepy if you're having trouble falling asleep.

How long does it take to work?

Lorazepam tablets and liquid start to work in around 20 to 30 minutes. It reaches full sedating effect after 1 to 1.5 hours and lasts for around 6 to 8 hours.

A lorazepam injection works much faster but also lasts around 6 to 8 hours.

How long will I take it for?

How long you take lorazepam for depends on why you're taking it:

  • anxiety and sleep problems – it's usually only recommended for up to 4 weeks. Your dose may be reduced gradually to prevent withdrawal symptoms.
  • before an operation or procedure – you will usually only need 2 doses.

If you're having a seizure or fit, you'll only be given a lorazepam injection while you're in hospital.

If a doctor prescribes lorazepam for more than 4 weeks, they'll tell you how long to take it for.

Will I become addicted to lorazepam?

Lorazepam is not likely to be addictive if you take it at a low dose for a short time (2 to 4 weeks).

You're more likely to become addicted if you have, or have previously had, problems with alcohol or drugs.

Speak to a doctor if you've had problems with alcohol or recreational drugs. They may want to try you on a different medicine.

What happens when I want to stop taking lorazepam?

If a doctor recommends you stop taking lorazepam, they will reduce your dose gradually. This will be done by reducing the number of tablets you take and how often you take them.

This allows your body to get used to being without the medicine and reduces the chance of side effects when you stop taking it.

This is important if you have been taking a high dose or a doctor has prescribed it for more than 4 weeks.

If you stop taking lorazepam suddenly, you may get side effects, such as:

  • confusion
  • having a seizure or fit
  • depression
  • feeling nervous or irritable
  • sweating
  • diarrhoea

If you get any of these side effects, speak to a doctor.


Do not stop taking lorazepam without talking to a doctor.

Are there other treatments I can try?

For anxiety, depending on your symptoms, you may need a medicine to treat your physical symptoms as well as your psychological ones.

Your doctor will usually start you on a type of antidepressant called a selective serotonin reuptake inhibitor (SSRI), such as sertraline, paroxetine or escitalopram.

There are also different types of talking therapies for anxiety, including cognitive behavioural therapy (CBT) and counselling.

For sleep, your doctor will discuss your condition with you and help you decide which medicine is best for you.

Can I drink alcohol with it?

Do not drink alcohol while you're taking lorazepam. Alcohol can increase the effects of lorazepam.

It can make you go into a very deep sleep. There's a risk you will not be able to breathe properly, and may have difficulty waking up.

Will recreational drugs affect it?

Using cannabis, heroin or methadone with lorazepam will increase the drowsy effects of lorazepam.

It can make you go into a very deep sleep. There's a risk you will not be able to breathe properly, and you may have difficulty waking up.

Using cocaine or other stimulants such as MDMA (ecstasy) and amphetamines with lorazepam can also lead to drowsiness.

Talk to a doctor if you think you might use recreational drugs while taking lorazepam.

Are there any foods and drink I need to avoid?

It's a good idea to avoid grapefruit or grapefruit juice while taking lorazepam. Grapefruit juice may increase the amount of lorazepam in your blood.

It's best to not have drinks such as coffee, tea and cola, or to eat a lot of chocolate because these contain caffeine. Caffeine is a stimulant and may reduce the calming effects of lorazepam.

Alcohol can increase the effects of lorazepam and make you go into a very deep sleep. It's important not to drink alcohol while you're taking lorazepam. There's a risk you will not be able to breathe properly, and you may have difficulty waking up.

Will it affect my contraception?

Lorazepam will not affect any contraception, including the combined pill and emergency contraception.

Some contraceptives may make lorazepam less effective. Talk to a doctor if you're taking a contraceptive and you think your lorazepam is not working very well.

Will it affect my fertility?

There's no evidence that lorazepam will affect fertility in either men or women.

Can I drive or ride a bike?

Do not drive a car or ride a bike if lorazepam makes you sleepy, gives you blurred vision, or makes you feel dizzy, clumsy or unable to concentrate or make decisions.

This may be more likely when you first start taking lorazepam, but could happen at any time (for example, when starting another medicine).

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.

Even if your ability to drive is not affected, the police have the right to request a saliva sample to check how much lorazepam is in your body.

GOV.UK has more information on the law on drugs and driving.

Talk to a doctor or pharmacist if you're unsure whether it's safe for you to drive while taking lorazepam.

Can lifestyle changes help with anxiety or insomnia?

If you have anxiety, lifestyle changes you can make to help ease your symptoms include:

If you're having trouble sleeping, things you can do to help yourself get better sleep include:

  • set regular times for going to bed and waking up
  • relax before bedtime, such as listening to some calming music
  • use thick curtains or blinds, an eye mask and earplugs to stop you being woken up by light and noise
  • avoid caffeine, cigarettes (including e-cigarettes), alcohol, heavy meals and exercise for a few hours before going to bed
  • do not watch TV or use phones, tablets or computers just before going to bed
  • do not nap during the day
  • write a list of your worries, and any ideas about how to solve them, before you go to bed to help you forget about them until the morning