Side effects
Like all medications, diazepam can cause some side effects, and in some cases they can be serious.
Most side effects, however, are mild and should get better within a few days.
If they do not, you should go back to your doctor.
Do not stop taking the tablets until you talk to your doctor, or you may get withdrawal symptoms.
Body
Diazepam does not usually affect your weight.
Sleep
Diazepam may make you feel very sleepy, and this can carry on into the next day.
Some people find it more difficult to get to sleep when taking diazepam or may experience nightmares or strange dreams when taking it.
If your sleep is negatively affected by diazepam, you should discuss this with your doctor.
Sex and fertility
Sex
Diazepam can have side effects that might affect your sex life. These include:
- losing interest in sex
- feeling ‘numb’ to your normal emotions
The good effects of diazepam may have a good effect on your sex life as your symptoms settle, you sleep better, and you can concentrate on your relationships.
If these symptoms don’t pass within a couple of weeks, and this is a problem for you, go back to the doctor and see what else you could try.
Fertility
There is no evidence to suggest that diazepam affects fertility.
Pregnancy, post-natal and breastfeeding
Pregnancy
If you are pregnant or trying for a baby, you should let your doctor know this before taking diazepam.
It’s not known whether diazepam affects the developing baby and causes any abnormalities, although the risk is thought to be low.
Babies often do better when their mums are mentally well, so if diazepam has beneficial effects on your mental health, it may be best to continue taking it throughout pregnancy. Your doctor can help you weigh up the pros and cons.
Post-natal
Taking diazepam during the last few months of pregnancy can cause withdrawal symptoms in a newborn baby that include weakness and breathing difficulties. Your baby may be less active than other babies, have a low body temperature, be floppy, or have breathing or feeding difficulties for a while. Your baby’s response to the cold might also be affected for a while.
Breastfeeding
Diazepam is passed to the baby in breast milk. This may help counter any withdrawal effects but may also make the baby too sleepy and unable to feed.
If you decide to take diazepam throughout your pregnancy, talk to your midwife or doctor.
Driving and transport
Diazepam can make you feel sleepy, dizzy and forgetful when you first start taking it. You might also find it difficult to concentrate during the first few days of treatment and may experience blurred vision and muscle weakness. For these reasons, you should not ride a bike or drive a car until you know how you will be affected.
You should also be very careful when doing anything else that requires concentration, such as operating machinery or exercising.
The effects of diazepam can last a while after taking it, so even if you only take one dose, you may feel them the next day. It’s important not to drive, ride a bike or operate machinery if you feel that your ability to concentrate has been compromised by taking diazepam.
Diazepam is in a group of medicines listed in new laws in the Road Traffic Act 1988. It is an offence to drive while under the influence of this medicine but you are NOT committing a crime if the medicine has been prescribed to you by a doctor, you are sticking to the prescribed dose and it is not affecting your ability to drive safely. The Department of Transport website has more details.
School and exams
Try not to take diazepam for the first time just before your exams.
Diazepam can affect your memory and make it harder to learn.
You may feel forgetful, very sleepy, and find it difficult to concentrate when you start taking diazepam.
You should talk to your doctor about any future exams if you are starting diazepam. You might decide together to delay starting it until you have done them.
If they are more than a few weeks away, however, you might find that it is better to start diazepam to improve your sleep.
Do not use caffeine drinks to stay awake for exam revision – they won’t stop the diazepam blunting your learning.
Friends and family
You may want to let your family and friends know you are taking diazepam so they can support you and help you look out for side effects.
For guidance on this, check out our page on getting support with your medication.
Sport
Diazepam is not a banned substance in sport.
However, diazepam has many side effects that might make you less able to take part in sports that need a lot of focus. These include feeling sleepy, blurred eyesight, being forgetful, muscle weakness and finding it difficult to concentrate.
The good effects of diazepam may enhance your sporting performance as your symptoms settle, and you sleep better.
Alcohol, street drugs and smoking
Alcohol
Be very careful drinking alcohol while taking diazepam.
You can drink a small amount of alcohol while taking diazepam but having the two together is likely to make you very sleepy. This will be most noticeable during the early part of your treatment.
Taking large amounts of alcohol and diazepam together could affect your breathing, especially if you have an existing lung problem.
If you need to drive a car or ride a bike, or use machines at work, taking alcohol and diazepam together could be dangerous to yourself and other people.
Street drugs
Diazepam does not mix well with street drugs.
It is very easy, and serious, to overdose with any combination of diazepam and drugs.
Using cannabis with diazepam will make its sedative effect worse. You could go into a very deep sleep where you do not breathe properly and have difficulty waking up.
Cannabis and other drugs may have their own side effects on your mental health, like anxiety or psychosis. For more information, have a look at our drugs and alcohol page.
Using heroin or methadone with diazepam will also increase their combined sedative effects. You could go into a very deep sleep where you do not breathe properly and have difficulty waking up.
Using cocaine or other stimulants (like ecstasy, amfetamines, MDA, 6-APB etc.) with diazepam is likely to lead to a reduced stimulant effect. This could lead you to increase the dose of the stimulant to make up for it, which could be very dangerous.
Smoking
If you start or stop smoking while you are taking diazepam, you may have to change your dose. This is because cigarette smoke affects the amount of diazepam in your body.
If you already smoke when you begin taking this medication, you will probably need a higher dose than somebody who does not smoke. You should tell your doctor if you smoke and how much, so that they can prescribe the correct dose for you.
If you stop smoking, the level of diazepam in the body could rise, and you might need to reduce your dose of diazepam slowly over one week.
If you (re)start smoking, you might need to increase it again.
Go to your doctor for advice if you stop or start smoking.
Prescription medicines
Diazepam may affect the way other drugs work. Tell your doctor or pharmacist if you are taking any other medicines. If you are taking any other medicines, some dose adjustments may be required to ensure you get the best from the diazepam with as few side effects as possible
Tell the pharmacist you are taking diazepam if you buy medicines over the counter for common complaints, including tablets and topical medicines (things you put on your skin).
Other interactions
Watch your caffeine intake while you are taking diazepam as caffeine has the opposite effect of diazepam in your body and interferes with it working.
Do not drink large amounts of caffeine drinks (like coffee, cola or energy drinks) while you are taking diazepam.
Caffeine can cause anxiety and sleep loss – stopping these drinks might help to improve your symptoms.
References and further reading
For more helpful links and information, have a look at our references and further reading page.
