Lorazepam

Lorazepam is a prescription medicine belonging to a group of medicines called benzodiazepines. In the UK, it may be prescribed for the short-term treatment of severe anxiety, anxiety-related sleeping problems, or as a medicine given before certain medical, dental or surgical procedures.

Lorazepam has a calming and sedating effect on the central nervous system. Because regular use can lead to dependence and withdrawal symptoms, treatment is usually kept short and should be reviewed by a healthcare professional.

Lorazepam at a Glance

Medicine	Lorazepam
Medicine type	Benzodiazepine
Main uses	Short-term treatment of severe anxiety, anxiety-related sleeping problems and premedication before some procedures
UK status	Prescription-only medicine
How it works	Enhances the effects of GABA, an inhibitory chemical messenger in the brain
How quickly it works	Oral lorazepam generally begins working within around 20-30 minutes
Treatment duration	Usually short term; for anxiety and sleep problems it is generally recommended for no longer than 4 weeks
Important considerations	Can cause drowsiness, impaired coordination, dependence and withdrawal symptoms
Alcohol	Alcohol should be avoided while taking lorazepam

What Is Lorazepam?

Lorazepam is a benzodiazepine medicine. Benzodiazepines reduce activity in parts of the central nervous system and can produce calming, sedating and muscle-relaxing effects.

Doctors may prescribe lorazepam when anxiety is severe enough to cause substantial distress or interfere with normal functioning. It can also be used for sleeping difficulties related to anxiety and as a premedication before certain procedures.

Lorazepam is not generally intended as a long-term treatment for everyday stress or mild anxiety. UK prescribing information recommends using it for the shortest appropriate period because continued use can increase the risk of tolerance, dependence and withdrawal.

It is available only on prescription in the UK.

What Is Lorazepam Used For?

Lorazepam has several recognised medical uses, although the reason for prescribing it depends on the individual patient.

Severe anxiety

Lorazepam may provide short-term relief from severe or disabling anxiety. It can reduce symptoms while a clinician assesses the underlying problem or while another treatment begins to take effect.

It is not normally considered appropriate for mild anxiety associated with ordinary day-to-day pressures.

Sleeping problems related to anxiety

Lorazepam can have a sedating effect and may sometimes be prescribed for short-term sleeping difficulties associated with anxiety.

Persistent sleep problems can have many causes. A clinician may therefore consider sleep habits, mental health, physical conditions and other medicines before deciding whether a benzodiazepine is appropriate.

Before medical or dental procedures

Lorazepam may sometimes be given as a premedication before an operation, dental treatment or another procedure. Its calming and sedative effects can help reduce anxiety beforehand.

Injectable lorazepam also has hospital uses, including treatment of certain seizures, but this is managed by healthcare professionals.

How Does Lorazepam Work?

Lorazepam acts on the central nervous system.

Its effects are linked to gamma-aminobutyric acid, usually shortened to GABA. GABA is a chemical messenger that reduces activity between nerve cells in the brain.

Lorazepam strengthens the inhibitory effects of GABA at GABA-A receptors. In simple terms, this makes certain nerve signals less active. The resulting effect can reduce anxiety and produce relaxation and sleepiness.

This same action explains why lorazepam can affect alertness, coordination and reaction time.

How Long Does Lorazepam Take to Work?

According to NHS medicine information, lorazepam tablets and oral liquid generally start working in around 20 to 30 minutes. The full sedating effect is usually reached later and may last for several hours.

This does not mean everybody experiences the medicine in exactly the same way. The effect can vary according to the reason it is being taken, the prescribed dose, age, other medicines and individual health factors.

Someone taking lorazepam should follow the timing given by their doctor or pharmacist rather than changing when or how much they take based on how quickly they feel an effect.

How Is Lorazepam Taken?

Lorazepam should be taken exactly as prescribed.

Tablets are swallowed with water and can generally be taken with or without food. Oral liquid preparations should be measured using the device supplied with the medicine rather than an ordinary kitchen teaspoon.

The appropriate dose depends on why lorazepam has been prescribed, as well as factors such as age, health and response to treatment. Older people and some people with liver or kidney problems may require different prescribing considerations.

Do not increase the prescribed dose because the medicine seems less effective. This can increase the risk of excessive sedation, dependence and other adverse effects.

Lorazepam prescribed for one person should never be shared with somebody else.

If a dose is forgotten, the appropriate action can depend on why lorazepam is being used and when the missed dose is noticed. NHS guidance advises against taking two doses to compensate for a forgotten dose. Check the patient leaflet or ask a pharmacist or prescriber if you are unsure.

Who May Not Be Able to Take Lorazepam?

Lorazepam is not suitable for everyone.

Before treatment, a doctor needs to know about existing medical conditions and other medicines. Particular care may be necessary for people with:

• breathing or chest problems
• sleep apnoea
• liver or kidney problems
• myasthenia gravis
• balance difficulties or a higher risk of falls
• glaucoma
• a history of alcohol or drug problems
• depression or previous thoughts of self-harm
• certain personality disorders
• previous reactions to lorazepam or other medicines.

Older adults can be more sensitive to sedating medicines and may have a greater risk of confusion, poor coordination and falls.

Pregnancy, plans to become pregnant and breastfeeding should also be discussed with the prescriber.

This is not a complete list. The clinician prescribing lorazepam should have an up-to-date record of relevant health conditions, prescription medicines, over-the-counter treatments and supplements.

Lorazepam Side Effects

Like other medicines, lorazepam can cause side effects, although they do not affect everyone.

Common or recognised effects

Daytime sleepiness is one of the better-known effects. Other recognised problems include:

• tiredness
• muscle weakness
• problems with coordination or movement
• dizziness or reduced alertness.

These effects matter particularly when driving, working at height or operating machinery.

Some people may also experience memory difficulties, particularly around the period when the medicine is having its strongest sedative effect.

Speak to a doctor or pharmacist if side effects persist, become troublesome or appear to be getting worse.

Serious Side Effects - When to Seek Medical Help

Serious reactions are uncommon but need appropriate medical attention.

Contact a doctor or NHS 111 promptly if symptoms such as hallucinations, unusual changes in behaviour, repeated falls or signs of liver problems occur.

Some people can experience unexpected behavioural reactions, including agitation, restlessness, irritability or aggression rather than sedation.

Call 999 or go to A&E if someone taking lorazepam develops severe breathing difficulty, very slow breathing, becomes unresponsive, or develops signs of a serious allergic reaction such as swelling of the lips, tongue, mouth or throat with difficulty breathing.

Taking more lorazepam than prescribed also requires urgent medical advice. NHS guidance advises contacting NHS 111 if more than the prescribed amount has been taken.

Lorazepam and Alcohol

Alcohol should be avoided while taking lorazepam.

Both substances depress activity in the central nervous system. Combining them can substantially increase sleepiness and impair judgement, coordination and alertness.

More importantly, the combination can cause unusually deep sleep and may affect breathing or make a person difficult to wake.

There is no sensible way to define a universally safe amount of alcohol to combine with lorazepam. Follow the advice provided with the prescription.

Lorazepam and Other Medicines

Lorazepam can interact with other medicines, particularly treatments that also cause sedation.

Examples that may require additional consideration include:

• opioid painkillers such as codeine, morphine, oxycodone or tramadol
• other sleeping or sedating medicines
• sedating antihistamines
• some antidepressants
• antipsychotic medicines
• anticonvulsants
• muscle relaxants
• certain antifungal medicines
• some medicines used to treat HIV
• medicines that can alter the way lorazepam is processed by the body.

Combining lorazepam with opioids can be particularly important because both can suppress the central nervous system and breathing.

Some herbal products used for sleep or anxiety, including valerian and passionflower, can also increase drowsiness.

Tell your doctor or pharmacist about all medicines, supplements and herbal products you use. Do not combine, stop or alter medicines without appropriate advice.

Driving After Taking Lorazepam

Lorazepam can cause sleepiness, dizziness, blurred vision, slower reactions, reduced concentration and problems with coordination.

Do not drive, cycle or operate machinery if you are affected.

Lorazepam is also one of the medicines covered by drug-driving legislation in Great Britain. Having a valid prescription does not make it acceptable to drive while impaired.

People who have been prescribed lorazepam should take it according to their healthcare professional's instructions and should not drive when the medicine makes them unfit to do so.

The rules in Northern Ireland differ from the specified-limit legislation applying in England, Wales and Scotland, although driving while impaired by medication can still have legal consequences.

Dependence, Tolerance and Withdrawal

Dependence is one of the main reasons lorazepam is generally used for a limited period.

Dependence

Physical dependence means the body adapts to the presence of the medicine. Psychological dependence can involve feeling unable to cope without taking it.

The risk tends to increase with higher doses and longer periods of treatment. A previous history of alcohol or drug problems can also be relevant.

Tolerance

With repeated benzodiazepine use, some people can develop tolerance. This means the effects of a particular dose may become less noticeable.

A person should not respond by increasing their dose independently.

Withdrawal

Stopping lorazepam suddenly after regular use can cause withdrawal symptoms. These may include anxiety, sleep disturbance, restlessness and other physical or psychological symptoms. More serious withdrawal effects can occur in some circumstances.

For this reason, a doctor may gradually reduce the dose when treatment is being stopped.

Anyone who has been taking lorazepam regularly should speak to their prescriber before stopping or substantially reducing it. A tapering plan needs to be individualised; there is no single schedule that is appropriate for everyone.

Pregnancy and Breastfeeding

Lorazepam use during pregnancy should be discussed with a doctor so that the benefits and possible risks can be considered for the individual situation.

NHS guidance notes that lorazepam can be used during pregnancy in some circumstances. Longer-term use, particularly towards the end of pregnancy, may affect the baby after birth and can be associated with withdrawal effects.

Lorazepam passes into breast milk in small amounts. NHS guidance indicates that it can sometimes be used while breastfeeding when the baby is healthy, following advice from a doctor, midwife or health visitor.

Anyone who is pregnant, planning a pregnancy or breastfeeding should tell their healthcare professional rather than starting, stopping or changing lorazepam without advice.

How Long Does Lorazepam Stay in Your System?

How long lorazepam affects someone is different from how long the medicine remains in the body.

The noticeable calming or sedating effect of oral lorazepam generally lasts for several hours. After that, the body continues breaking down and eliminating the medicine.

Lorazepam has an elimination half-life measured in hours rather than simply disappearing when its sedating effect wears off. The exact time varies according to age, metabolism, health, dose and other medicines.

Laboratory tests may sometimes detect a medicine or its metabolites after the noticeable effects have passed. Detection windows also depend heavily on the type of test being used, so they should not be used as a measure of whether someone is safe to drive or carry out safety-sensitive activities.

Lorazepam vs Diazepam

Lorazepam and diazepam both belong to the benzodiazepine family, but they are not interchangeable medicines.

Feature	Lorazepam	Diazepam
Medicine class	Benzodiazepine	Benzodiazepine
Anxiety treatment	Used in selected cases	Used in selected cases
Sedating effects	Yes	Yes
Prescription required in UK	Yes	Yes
Dependence risk	Present	Present
Withdrawal risk	Present	Present

They differ in areas including their duration of action, approved uses, metabolism and dosing. A milligram of one benzodiazepine should not be assumed to be equivalent to a milligram of another.

Patients should not switch between lorazepam and diazepam without clinical guidance.

Getting Lorazepam in the UK

Lorazepam is a prescription-only medicine in the UK.

A clinician needs to decide whether it is appropriate after considering why the medicine is needed, the severity and duration of symptoms, medical history, other medicines and potential risks.

For anxiety or sleeping problems, treatment is normally intended to be short term. Longer-term anxiety or persistent insomnia may need a broader treatment plan rather than continued benzodiazepine use.

Prescription medicines should be obtained through legitimate UK healthcare and pharmacy services. When medicines are supplied through an online pharmacy, patients can check whether the pharmacy is appropriately registered with the relevant UK regulator.

An online questionnaire or consultation does not automatically mean lorazepam will be prescribed. The prescriber must make a clinical decision about whether treatment is appropriate.