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