Dexamfetamine

Medication name

Dexamfetamine ("DEX-am-FET-a-meen")
Brand name

Amfexa ("am-FEX-a")
Medication type

Central nervous stimulant

Tablets: 5mg, 10mg and 20mg strengths

Liquids: 1mg/ml (one 5ml spoonful of the oral solution is like one 5mg tablet)

If you are aged six to 18 years, the doctor can prescribe dexamfetamine for you as a licensed medicine for treatment of attention deficit hyperactivity disorder (ADHD).

If you are aged 18 years or over, a specialist doctor may still consider this as a treatment option for ADHD.

Dexamfetamine can be used in adults who have narcolepsy, where they fall asleep too easily and without warning.

Read our guide to ADHD and mental health

About dexamfetamine

Dexamfetamine is a central nervous stimulant (CNS). Dexamfetamine can also be called a dopamine and noradrenaline reuptake inhibitor. This describes how it works in the brain.

It might seem odd that you would use a stimulant as a treatment for hyperactivity, but in people with ADHD, stimulant medicines do not make them more active as they do in other people. Instead these medicines will help to improve concentration, ability to focus and help with behaviour and other activities like the ability to plan, organise time, manage emotions and make decisions.

Dexamfetamine stimulates centres in the brain that are underactive in people with ADHD, like the bits of the brain involved with concentration.

Noradrenaline and dopamine are two naturally occurring chemical messengers (or ‘neurotransmitters’) that have an important role in areas of the brain that control mood thinking, feelings, emotions and perception. Dexamfetamine works by blocking these chemical messengers from being taken back up into the nerve cells in the brain after being released. Dexamfetamine also mimics the action of these two chemicals, acting as a substitute.

This results in higher levels of noradrenaline and dopamine between the nerve cells and allows these chemicals to hang around for longer.
With higher levels of noradrenaline and dopamine in the brain, many other effects occur in different parts of the body, including the heart, the gut, and the lungs. Overall, this leads to the good effects of the medicine, but can also produce unwanted side effects.

When used to treat narcolepsy, increased levels of dopamine and noradrenaline help people to stay awake and alert.

Dexamfetamine is a 'controlled drug'

This is because there is an increased risk of the medicine being supplied or sold illegally and misused.

Dexamfetamine is a stimulant, so some people want to use it as a drug to get high or as a ‘performance-enhancer’ to help them work harder or revise for exams. There is little or no evidence to show this works and it could cause serious side effects if taken by people who are not prescribed this medicine.

Sometimes people taking dexamfetamine from their doctor may be targeted at school and bullied to give away or sell their medicine.

If someone is asking you to give away or sell your medicine, please ask your parent, teacher or doctor to help you. Never share (or sell) your medicine to anyone else. This is dangerous and illegal.

If you must take it to school, check with your teachers how to keep your medicine safe until you need it.

There are special rules and laws for how controlled drugs are prescribed.

The doctor must write extra information on the prescription, like the total amount needed in words and figures to make it harder for a genuine prescription to be altered.
A prescription for dexamfetamine must be dispensed by the pharmacy and collected within 28 days of the prescription being written. Other prescriptions for medication that isn’t a controlled drug are valid for up to six months.
You cannot get an emergency supply of dexamfetamine without a prescription.

Dexamfetamine and everyday life

Dexamfetamine can start to work after the first dose, but may take a few weeks to show its full effect.

You should see improvements in your concentration and other symptoms within one month of starting the medicine, usually within the first week of taking it.

Your doctor might start you on a low dose and then increase it slowly over two to four weeks, sometimes longer. The doctor will monitor your symptoms and find the dose that works best for you.

Dexamfetamine can make you want to eat less, so you may lose weight while taking it.

Some people gain weight, but weight loss is more common.

Dexamfetamine can also affect your growth.

Your doctor will check your weight and height at least every six months while you are taking dexamfetamine. If you are not growing as fast as your friends, the doctor may stop the dexamfetamine for a while to let your growth recover.

It is not possible to predict how dexamfetamine will affect each person who takes it. Talk to your doctor before starting this medication if you have concerns about how it might affect your weight and growth.

A common side effect of dexamfetamine is a dry mouth. Over a long time, this can increase your risk of developing tooth decay or gum disease. Make sure you brush your teeth well and have regular dental check-ups. Speak to your dentist, doctor or pharmacist about things you can do to help.

You may want to let your family and friends know you are taking dexamfetamine 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.

Dexamfetamine is a stimulant and can therefore affect your sleep by keeping you awake. Talk to your doctor about this if it is a problem for you.

You should take your tablets early in the day, and no later than lunchtime or early afternoon, to get the best chance of sleeping normally.

Depending on your lifestyle, studying or work, you may find taking a dose of your medication later in the day manages your symptoms better in the evening and helps you more. Discuss this with your doctor to work out what works best for you.

If the medication helps to improve your ADHD symptoms, this may also help to improve your sleep.

Alcohol

Drinking alcohol while taking dexamfetamine can strengthen the effects of the medication, which may give you side effects similar to taking too much of it.

It is recommended that you don’t drink alcohol until you know how the medicine affects you.

If you decide to drink alcohol, only drink in small amounts and see how it affects you.

When combined, dexamfetamine and alcohol can cause unpredictable effects. The combination may increase your blood pressure and heart rate. Dexamfetamine can also reduce the effects of alcohol which may mean you end up drinking more than you realise which could be very dangerous.

It is advisable not to drink alone, so that there is someone else there to help you if you need it.

Drinking alcohol every day, or in large amounts, can make your symptoms worse and may mean you won’t get the maximum benefit from your medication.

Remember that some foods also contain alcohol.

Street drugs

Dexamfetamine is dangerous to take with cocaine or ecstasy or other amfetamines. This is because they are all stimulants and may together put too much pressure on your heart and the blood vessels in your brain.

Mixing methadone with dexamfetamine can cause serious heart problems and may trigger a dangerous condition known as serotonin syndrome.

Dexamfetamine may add to the pain-killing effects of heroin. You might hurt yourself and not feel enough pain to get help.

Dexamfetamine is also known as a street drug as it’s a stimulant, so some people use it to get ‘high.’

People taking dexamfetamine from their doctor can be targeted at school and bullied to give away or sell their medicine. If this happens to you, ask your parent, teacher or doctor to help you. Never share or sell your medicine to anyone else – this is dangerous and illegal.

This medicine may give a positive result when testing for drug use. Talk to your doctor if this is a problem for you.

There are many other street drugs, but we don’t know what effect taking them with dexamfetamine will have, so it’s best to be cautious. There is no regulation of street drugs or ‘legal highs’, so even if there are no known issues with the medication you take, the supply you receive might be mixed with other substances that could be dangerous.

Get more advice on drugs and alcohol.

Dexamfetamine does not mix well with some other medicines and herbal remedies.

Do not take dexamfetamine if you have taken a monoamine oxidase inhibitor antidepressant (MAOI) like moclobemide, phenelzine, isocarboxazid or tranylcypromine in the last 14 days.

Taking a MAOI with dexamfetamine may cause a sudden and dangerous increase in your blood pressure.

If you are taking other medicines, dexamfetamine may affect how well they work or may cause side effects. Tell your doctor about these before you start your treatment.

Talk to your pharmacist if you buy any medications over the counter to treat common illnesses like colds and flu, or medications that you put on your skin.

Look at the leaflet inside your medicine box for more information about other medicines that can interact with dexamfetamine. With some medicines your doctor may need to adjust the dose of your medicines if you take them together. Ask a doctor or pharmacist for more information if you have any questions.

The oral solution is likely to be sugar-free but may have some preservatives in it that can cause allergies. Talk to your pharmacist if you have problems with food additives or ‘E’ numbers.

Some dexamfetamine tablets may contain lactose and isomalt. Check with your pharmacist if these ingredients are a concern for you.

Always let your pharmacist know if you have any food allergies or intolerances, and always check with them if you’re concerned about any of the ingredients in your medication.

If you need to avoid animal products, please note that non-active ingredients used in the production of medicines may sometimes be of animal origin. Ask your pharmacist if you have any questions about the ingredients.

Further information about practical considerations for medicines if you need to avoid animal products can be found on the Vegan Society website.

Taking dexamfetamine may give you blurred vision, make you feel drowsy or dizzy, make it difficult to concentrate or affect your focus when you start taking it.

It may be best to stop doing things like driving a car, riding a bike, or anything else that needs a lot of focus for the first few days, until you know how it affects you.

Most people drive as normal while taking dexamfetamine. If you are worried about this or have any concerns you would like to discuss, speak to your doctor or pharmacist.

You must tell DVLA if your ADHD or your ADHD medication affects your ability to drive safely. If you think you driving might be affected by your ADHD or your medication, don’t drive and speak to your doctor. It is illegal to drive with medication in your body if it impairs your driving. You do not need to tell DVLA about your condition unless you think that it may affect your ability to drive safely. Ask your doctor if you’re not sure if your condition will affect your driving.

You may also have to prove that you have been given dexamfetamine on prescription, so you should keep your repeat prescription slip or get a letter to explain it from your doctor.

Pregnancy

If you become pregnant while you are on dexamfetamine, you should carry on taking it and make an appointment to see your doctor as soon as possible. They can discuss the benefits and risks of continuing dexamfetamine and help you to make a decision that is best for you and your baby. They may refer you to a specialist perinatal mental health team to support you with this decision.

You can find out more information about taking dexamfetamine during pregnancy at Bumps (Best Use of Medicines in Pregnancy).

We know very little about its effects on a developing baby, but studies suggest amfetamines do not increase the risk of malformations.

Available data suggests that there might be an increased risk of preeclampsia (high blood pressure) and premature birth.
If you are planning to get pregnant, it is recommended that you take folic acid while you are trying for a baby and during pregnancy. It is safe to take this together with dexamfetamine.

Post-natal

If you agree with your doctor to carry on taking dexamfetamine, you should tell your midwife that you are taking it as soon as possible.

Babies exposed to dexamfetamine during pregnancy may experience withdrawal symptoms and have a lower birth weight.

There are some other symptoms that can occur in newborn babies if dexamfetamine is taken during pregnancy. Your baby may need additional observations and support following delivery. Discuss this with your midwife as part of your birth plan. Look out for these and get help if they happen:

jerking or twitching of the muscles or shaking
being jittery, irritable or constant crying
being too hot or cold
suckling/ feeding difficulties or being sick
having stiff or floppy muscles, or overactive reflexes
being very sleepy or finding it difficult to sleep

These symptoms are usually mild and only last a few hours to a few days.

Breastfeeding

Dexamfetamine can be passed to the baby in breast milk and the amount detected can vary.

Remember that it is important for you to stay well while you are bonding with and looking after your baby. This means that you may need to take dexamfetamine or another medicine for your mental health and wellbeing when breastfeeding.

If, after discussing this with your doctor, you decide the best option is to continue dexamfetamine, take the lowest dose that keeps you well and monitor your baby carefully for symptoms of irritability, sleeping difficulties, poor feeding and weight loss. Seek advice from your midwife, health visitor or doctor if you are concerned.

If your baby was born early or has health problems, then breastfeeding while you are taking dexamfetamine may not be recommended. Talk to your midwife and doctor about feeding options.

Sex

Dexamfetamine can have side effects that might affect your sex life. These include:

wanting to have sex less or losing pleasure in having sex
difficulty getting an erection (getting hard)
losing weight (if this affects your body confidence)

Most side effects occur when you first start medication and improve over time. If they do not, and this is a problem for you, make an appointment to discuss this with your doctor.

If it works for you, dexamfetamine may have a positive effect on your sex life as your symptoms settle, and you can concentrate on your relationships.

Fertility

There is currently no evidence to suggest that dexamfetamine affects fertility.

Talk to your doctor about your dexamfetamine if you are trying to get pregnant.

Dexamfetamine is a stimulant which is included in the World anti-doping International Standard Prohibited List for Sports.

Dexamfetamine and other stimulants for ADHD are only prohibited in competition (not prohibited at all times).

If you play sport to a high level, and want to compete where testing will happen, you will need to ensure that you follow the correct procedure about informing regulators. You must not take Dexamfetamine during competitions. Check carefully how long before the event you need to stop your medication.

If this is a problem for you, you may want to discuss other treatment options for managing your ADHD with your specialist doctor.

When you first start taking dexamfetamine, you may feel tired, dizzy or get blurred vision, which may make it difficult in some sports. It might be best to stop doing those sports for a short time until you know how the medicine affects you or until the side effects improve.

Ideally, it is best not to take dexamfetamine for the first time just before your exams.

Most people take exams as normal while taking dexamfetamine. However, it is not possible to predict how the medication will make you feel, and if you do get any side effects, including feeling very tired or drowsy and blurry eyesight, these are more likely to occur when you first start taking it.

You should talk to your doctor about any future exams if you are starting dexamfetamine. You might decide together to delay starting it until you have done them. If they are more than a month away, however, you might find that it is better to start dexamfetamine to improve your motivation and ability to study.

If you are worried that taking dexamfetamine might make studying for or taking your exams harder, discuss this with your doctor.

Information and safety considerations

Your doctor will consider any other medical conditions or symptoms you have before recommending a medicine for you.

Your medicine will come with a ‘patient information leaflet’. It’s important that you read this information. Speak to your pharmacist if:

you’re not given a leaflet
you don’t understand the information
you need it in a different format or language
you’re concerned about something you’ve read

The information leaflet also includes a list of warnings and precautions to consider before you take the medicine. If you think that any of these apply to you and are concerned that your doctor is not already aware of them, check with your doctor or pharmacist before you start to take your medication (or as soon as possible if you are already taking it).

Uses, warnings, safety and side effects

Taking dexamfetamine

It is likely that you will take dexamfetamine for several years or more. If you start this medicine when you are under 18 years old, it may still help you when you are an adult.

Your specialist doctor should review your treatment regularly with you (at least once a year) and discuss whether you think the medicine is still helping you.

You and your doctor may agree to try a break in treatment (sometimes called a ‘drug holiday’) to see how you feel. This can help you to decide whether it would be best to continue with your medicine or not.

You will get the best effect from your dexamfetamine if you take it regularly at the dose prescribed by your doctor.

You might have to take dexamfetamine up to four times a day.

Avoid taking your dexamfetamine doses after 4pm. If you take dexamfetamine after 4pm, it could make it harder for you to get to sleep.

However, if your ADHD symptoms are better controlled, this may help you sleep better. So, depending on your lifestyle, college and work schedule, you may find taking a dose later in the day helps you.
You can take dexamfetamine with or without food.

If you need to break a tablet to get your exact dose, please ask the pharmacist how to do this accurately.

If your medication helps you but you feel like the benefits wear off during the day, talk to your specialist doctor about how to manage this.

Do not alter the dose of your medication yourself. Always speak to your doctor if you don’t think your medicine is working as well for you.

Once you remember, take it as soon as possible.

If you do not remember to take it before the next dose, just leave it and take the next dose. Do not try and catch up by taking a double dose.

If you forget to take it for a few days, your symptoms may come back. You may get an unwanted effect of feeling very low as the chemicals in your brain change their balance, with less noradrenaline and dopamine around. You may also feel very tired.

If you miss doses, even if you didn’t mean to, it is helpful to record how you managed during the day and how you felt. This will be useful to share with your doctor when they next review your medication with you.

You can stop taking dexamfetamine safely and gradually with your doctor’s help.

If you are on a low dose, you will be able to stop it suddenly. If you are on a higher dose, it may be better to reduce the dose before stopping it.

It is safe to stop this medication suddenly, but stopping it abruptly, or reducing the dose too much at once, may cause uncomfortable withdrawal symptoms. These may include feeling tired, low mood or irritability, increased appetite, aches and pains.

Not everyone experiences these, but it is important to be aware of them so you know what to look out for. They are caused by the brain adjusting to not having the medicine, and some may be due to a return of ADHD symptoms.

Your ADHD symptoms could return, or the sudden drop in noradrenaline and dopamine in your brain could bring on symptoms of depression and extreme tiredness. If you do experience any withdrawal symptoms they should stop after a few days. If they do not, or they are stopping you getting on with your life, discuss this with your doctor.

Warnings and safety

If you have taken more than the dose prescribed by your doctor, contact NHS 111 immediately to ask for advice, or ask a family member or friend to do this for you. This is important even if you don’t feel any different.

NHS 111 can give you advice and direct you to the best place to get more help if you need it.

If you have taken too much medication on purpose, or if after taking this you quickly feel unwell, call 999 or get someone to take you to A&E straight away. This includes any of the following signs:

feeling very excited
having a seizure or fit, which can lead to a coma
hallucinating (seeing, feeling or hearing things that are not real)
changes in your heartbeat (slow, fast or uneven)
your breathing getting slower

If you need to go to A&E, do not travel alone or drive yourself there. Get your parent, family member or friend to go with you to support you and keep you safe on the way. If someone is not able to drive you there, call for an ambulance. Take your medication with you and tell doctors how much you have taken.

Serious side effects

Dexamfetamine can cause serious side effects, including allergic reactions.

Stop taking dexamfetamine and go to a hospital straight away if you get any of the following symptoms:

difficulty breathing or talking, wheezing and tightness in the chest or throat
an allergic reaction or allergy (including symptoms such as high body temperature, swelling of your face, eyelids, lips, tongue or throat so that you cannot swallow or breathe, really bad itching of the skin with raised lumps)
a rash or hives where the skin is itchy, red swollen, blistered or peeling (the rash may be circular in appearance which is darker in the middle and lighter around the outside)
fast, uneven heartbeat and fainting (this could mean a life-threatening condition called Torsades de Pointes)
having seizures or fits

Get your parent, family member or friend to take you or go with you to support you and keep you safe on the way. If someone is not able to drive you there, call for an ambulance. Take your medication with you.

Contact your doctor immediately but don't stop taking dexamfetamine, if you get any of the following symptoms:

concerns about weight loss, weight gain, or slower growth
any changes or worsening of your mood or behaviour
feeling or hearing things that are not real or believing things that are not true
your behaviour changes because you feel very happy or over-excited
uncontrolled speech or body movements
uneven or racing heartbeats that feel like thumping inside your chest
unexplained rise in body temperature

If you are unable to contact your doctor, call NHS 111 for urgent advice.

Side effects and your health

Side effects are more common when you first start taking a new medicine. Many go away as you continue your medicine. If they don’t get better, or if you are worried by them and they are causing you distress, speak to your doctor, specialist team or pharmacist about them.

Very common side effects of taking dexamfetamine (affecting more than one in ten people) include:

disturbed sleep
feeling anxious or nervous
decreased appetite leading to lack of normal weight gain and possibly weight loss

Common side effects of taking dexamfetamine (affecting up to one in ten people) include:

feeling unusually happy
feeling irritable or aggressive
feeling confused or having a low mood (depression)
cramps or pain in your gut
feeling sick
dry mouth and changes in how you taste things
heart and blood pressure changes, including fast heart rate
rashes or itching skin
muscle pain

There are other side effects that you can get when taking this medicine. We have only included the most common ones here.

This list of side effects can look scary. You may not experience any of them, but it’s important to be aware of them so you know what to do if they do happen.

Unless your side effects are very severe or distressing, try to continue taking your medication until you can talk to your doctor. Your doctor can make changes to your medication to help if needed.

Additional monitoring is recommended with this medicine to check for any unwanted changes the medicine might cause and make sure your doctor can review them quickly.

Before you start taking dexamfetamine, if you change your dose, and at least every six months after you start, the doctor will do some tests to check that dexamfetamine is still right for you.

They will check your appetite, as dexamfetamine can make you want to eat less.

They will check your weight and height, as dexamfetamine can slow down your growth.

They will check your heart rate and blood pressure, as dexamfetamine can sometimes increase these.

They will ask you about your mood and how you are feeling to check that the medicine is working, but also whether you are having any side effects.

They will ask you about any feelings of aggression or dislike towards others, which can be a side effect of the medicine.

Before starting dexamfetamine your doctor may also check your heart using an electrocardiogram (ECG).