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ADHD Medication

Dexamfetamine Sulfate

Brand Name:
Amfexa

Dexamfetamine sulfate is a stimulant medication used to help manage symptoms of ADHD. It can help with attention and concentration and may reduce impulsivity and hyperactivity.

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Your Dose

Your clinician will agree your starting dose with you and increase it gradually if needed

Commences with 5mg twice a day, then increased under the guidance of a clinician at weekly intervals following review of effectiveness.

Maintenance dose given in 2 to 4 divided doses, maximum daily dosage of 60mg. 

The aim is to find the lowest dose that gives you good symptom control with manageable side effects.

Always take dexamfetamine exactly as prescribed. Do not change your dose without speaking to your prescribing clinician.

Before taking Dexamfetamine

Before starting dexamfetamine, tell your clinician about any physical or mental health conditions you have, even if they are well controlled or you have experienced them in the past.

Certain medical conditions may mean that dexamfetamine is not suitable for you. Others may require additional assessment, specialist advice or closer monitoring before treatment can begin.

It is particularly important that your clinician knows if you have, or have previously had:

  • Heart problems, high blood pressure or circulation problems
  • A stroke, aneurysm, advanced arteriosclerosis (hardening of the arteries) or another blood vessel condition
  • Phaeochromocytoma (a rare tumour of the adrenal gland)
  • Porphyria (a rare condition affecting the production of haem)
  • An overactive thyroid
  • Glaucoma
  • Epilepsy or seizures
  • Tics or Tourette's syndrome
  • An eating disorder, including anorexia nervosa
  • Bipolar disorder, psychosis or schizophrenia
  • Severe depression or suicidal thoughts
  • Kidney problems
  • A history of alcohol or drug dependence or misuse

Important: Dexamfetamine must not be used in certain medical conditions, including some serious heart conditions, anorexia nervosa, psychotic disorders and certain severe mood disorders.

If you have any of these conditions, your clinician will need to assess your medical history carefully and determine whether dexamfetamine is appropriate for you. This may require additional specialist assessment or discussion with a multidisciplinary clinical team.

Do not start taking dexamfetamine until your clinician has reviewed your medical history and confirmed that it is appropriate for you.

Other medicines

Dexamfetamine can interact with other medicines, sometimes causing serious side effects.

Tell your clinician about everything you take, including prescription medicines, over-the-counter medicines, vitamins, supplements, herbal remedies such as St John’s wort, and recreational drugs.

This is particularly important for:

  • Certain antidepressants

  • Medicines for blood pressure or heart conditions

  • Antipsychotic medicines

  • Epilepsy medicines

  • Anticoagulants (blood-thinning medicines)

  • Opioid painkillers, particularly tramadol and pethidine

  • Triptan medicines used to treat migraines

  • Some cough and cold remedies

Some medicines called monoamine oxidase inhibitors (MAOIs) must not be taken with dexamfetamine or within 14 days of taking dexamfetamine.

If you are unsure whether something is safe to take, check with your clinician or pharmacist first.

Full list of medicine interactions

Acenocoumarol 

Apraclonidine 

Atomoxetine 

Bupropion 

Chlorpromazine 

Citalopram 

Clomipramine 

Dapoxetine 

Duloxetine 

Escitalopram 

Fenfluramine 

Fentanyl 

Fluoxetine 

Fluvoxamine 

Imipramine 

Isocarboxazid 

Levomepromazine 

Linezolid 

Methadone 

Methylthioninium chloride 

Moclobemide 

Nabilone 

Nirmatrelvir 

Paroxetine 

Pentazocine 

Pericyazine 

Pethidine 

Phenelzine 

Prochlorperazine 

Promazine 

Rasagiline 

Ritonavir 

Safinamide 

Selegiline 

Sertraline 

Sevoflurane 

St John’s wort 

Tapentadol 

Tramadol 

Tranylcypromine 

Trazodone 

Trifluoperazine 

Tryptophan 

Venlafaxine 

Vortioxetine 

Warfarin 

Surgery and anaesthesia

If you are due to have an operation or medical procedure, tell your surgeon and anaesthetist that you are taking dexamfetamine.

Dexamfetamine can interact with certain anaesthetic medicines and may cause a sudden increase in blood pressure.

Your medical team may advise you not to take dexamfetamine on the day of your operation, depending on the type of anaesthetic being used.

Always follow the instructions given by your surgical or anaesthetic team. Do not change your medication without discussing it with them first.

Serotonin syndrome – important safety information

Dexamfetamine can increase serotonin activity in the brain. When taken with certain other medicines, it can rarely cause serotonin syndrome, a potentially serious reaction.

The risk may be increased when dexamfetamine is taken with:

  • Antidepressants, including fluoxetine, sertraline, escitalopram, venlafaxine and mirtazapine

  • Lithium, including lithium carbonate and lithium citrate

  • Monoamine oxidase inhibitors (MAOIs), which must not be taken with dexamfetamine or within 14 days of MAOI treatment

  • Certain strong painkillers, including tramadol and pethidine

  • Triptan medicines used to treat migraines

  • The herbal remedy St John’s wort

Always tell your clinician about every medicine, supplement or herbal remedy you take.

Recognising the symptoms

Early symptoms of serotonin syndrome may include:

  • Agitation or confusion

  • Sweating, shivering or fever

  • Tremor, muscle twitching or jerking

  • Overactive reflexes

  • Diarrhoea

  • A racing heart

Seek urgent medical advice if you develop symptoms of serotonin syndrome.

When to call 999

Call 999 immediately if you develop severe symptoms, including a high temperature, seizures, an irregular heartbeat or loss of consciousness.

Side Effects

Like all medicines, dexamfetamine can cause side effects. Not everybody will experience them.

Side effects are often most noticeable when treatment starts or when your dose changes.

Tell your clinical team if side effects are bothering you, getting worse or affecting your day-to-day life.

Reduced appetite

Difficulty sleeping

Feeling nervous or anxious

Headache or dizziness

Dry mouth

Nausea or vomiting

Increased heart rate

Changes in blood pressure

Irritability or mood changes

Full list of Side Effects

Common / very common
Abdominal pain
Anxiety
Appetite decreased
Arrhythmias
Arthralgia
Behaviour abnormal
Depression
Dry mouth
Headache
Mood altered
Movement disorders
Muscle cramps
Nausea
Palpitations
Poor weight gain
Sleep disorders
Vertigo
Vomiting
Weight decreased

Rare / very rare
Anaemia
Angina pectoris
Cardiac arrest
Central nervous system vasculitis
Cerebrovascular insufficiency
Fatigue
Growth retardation
Hallucination
Hepatic coma
Hepatic function abnormal
Intracranial haemorrhage
Leucopenia
Mydriasis
Psychosis
Seizure
Skin reactions
Suicidal behaviours
Thrombocytopenia
Tic (in those at risk)
Vision disorders

Frequency not known
Acidosis
Alopecia
Cardiomyopathy
Chest pain
Circulatory collapse
Colitis ischaemic
Concentration impaired
Confusion
Diarrhoea
Dizziness
Drug dependence
Hyperhidrosis
Hypermetabolism
Hyperpyrexia
Kidney injury
Myocardial infarction
Neuroleptic malignant syndrome (discontinue—potentially fatal)
Obsessive-compulsive disorder
Reflexes increased
Rhabdomyolysis
Sexual dysfunction
Sudden death
Taste altered
Tremor

Get urgent medical help:

Seek urgent medical advice if you develop serious or unexpected symptoms, including:

  • Hallucinations or symptoms of psychosis
  • Suicidal thoughts or behaviour
  • Severe or unexplained chest pain
  • A seizure
  • Severe muscle pain, weakness or cramping
  • Swelling of your face, lips, tongue or throat
  • Difficulty breathing or swallowing

Call 999 if you think you are experiencing a medical emergency.

A full list of possible side effects is available in the Patient Information Leaflet supplied with your medication.

Reporting side effects

If you experience any side effects while taking dexamfetamine, speak to your clinician or pharmacist. This includes any possible side effects not listed on this page or in the Patient Information Leaflet supplied with your medication.

You can also report suspected side effects directly to the Medicines and Healthcare products Regulatory Agency (MHRA) through the Yellow Card scheme.

Report online at yellowcard.mhra.gov.uk or use the MHRA Yellow Card app.

Reporting suspected side effects helps improve the safety of medicines for everyone.

Taking the medication

If you miss a dose

Do not take a double dose.

If you miss a dose, skip it and take your next dose at the usual time unless your clinician has given you different instructions.

If you take too much

Taking too much dexamfetamine can be serious and may require emergency medical treatment.

Signs of an overdose may include:

  • Severe agitation, restlessness or confusion

  • Tremor, muscle twitching or seizures

  • A rapid or irregular heartbeat

  • Chest pain

  • High temperature or excessive sweating

  • Nausea, vomiting or diarrhoea

  • Hallucinations or unusual behaviour

If you take more dexamfetamine than you have been prescribed, seek medical advice immediately, even if you feel well.

When to call 999

Call 999 immediately if you or someone else experiences severe symptoms following a suspected overdose, including seizures, chest pain, collapse, loss of consciousness or difficulty breathing.

Do not drive yourself to hospital. Take your medication packaging with you if possible.

Stopping dexamfetamine

Do not stop taking dexamfetamine suddenly without discussing it with your prescribing clinician.

Stopping treatment abruptly can cause withdrawal symptoms, including extreme tiredness, low mood, agitation, changes in sleep and increased appetite.

Your clinician may recommend reducing your dose gradually to help minimise withdrawal symptoms and monitor any return of your ADHD symptoms.

If you are considering stopping treatment or are experiencing difficulties with your medication, speak to your clinician so they can advise you on the safest approach.

Alcohol

You should not drink alcohol while taking dexamfetamine.

Alcohol can increase the risk of side effects and may affect your judgement, coordination and ability to recognise how much alcohol you have consumed.

Combining alcohol with dexamfetamine may also increase the risk of unwanted effects on your heart rate, blood pressure and nervous system.

Speak to your clinician if you have any questions about alcohol and your medication.

Driving

Dexamfetamine can affect your ability to drive safely, particularly if it causes dizziness, drowsiness, blurred vision or changes in concentration.

Do not drive until you know how the medication affects you. You must not drive if your ability to drive safely is impaired.

Driving and the law

Dexamfetamine is a controlled drug and may produce a positive result on a roadside drug screening test.

It is an offence to drive with certain controlled drugs above specified limits in your body. However, a statutory medical defence may apply if the medication has been prescribed for you, you have taken it in accordance with your prescriber’s instructions and the supplied information, and your driving is not impaired.

It is advisable to carry evidence of your prescription, such as a repeat prescription slip or a letter from your clinician.

You must inform the DVLA if your ADHD or medication affects your ability to drive safely.

Pregnancy and breastfeeding

Tell your clinician if you are pregnant, think you might be pregnant, are planning a pregnancy or are breastfeeding.

Your clinician will discuss the potential benefits and risks of continuing dexamfetamine and help you decide on the most appropriate treatment for your circumstances.

Pregnancy and contraception

If you could become pregnant, discuss contraception and pregnancy planning with your clinician before starting dexamfetamine.

If you become pregnant while taking dexamfetamine, contact your clinician as soon as possible. Do not stop taking your medication without medical advice.

Possible risks during pregnancy

There is limited information about the effects of dexamfetamine during pregnancy.

Studies involving exposure to amphetamine medicines during pregnancy have suggested a possible increased risk of pre-eclampsia (high blood pressure during pregnancy) and premature birth.

Babies exposed to amphetamine medicines during pregnancy may also experience withdrawal symptoms after birth.

Your clinician will consider these potential risks alongside the benefits of treatment and discuss the safest approach for you and your baby.

Breastfeeding

Dexamfetamine can pass into breast milk and may affect your baby.

Breastfeeding while taking dexamfetamine is generally not recommended. Your clinician can discuss your individual circumstances and the available treatment and feeding options.

If treatment continues while breastfeeding under specialist medical supervision, your baby may need monitoring for feeding difficulties, irritability, sleep problems or poor weight gain.

Drug screening and laboratory tests

Drug screening

Dexamfetamine may produce a positive result on workplace or roadside drug screening tests. If you are required to undergo drug testing, inform the relevant healthcare professional or testing provider that you are taking prescribed dexamfetamine.

Laboratory tests

Dexamfetamine can interfere with certain laboratory tests, including some tests that measure steroid levels. Tell your clinician that you are taking dexamfetamine before undergoing blood or urine tests.

Instructions

Dexamfetamine sulfate is a Schedule 2 controlled drug

Your pharmacy may ask you to provide proof of identity when you collect it, so we recommend taking photo ID with you.

Keep your medication somewhere safe and secure. Never give it to anyone else, even if they have similar symptoms.

Keeping treatment safe

While taking dexamfetamine, you will need regular reviews. Your clinical team may monitor:

Your clinical team may monitor:

  • Your blood pressure

  • Your pulse

  • Your weight

  • Your height and growth, if you are under 18

  • How well the medication is working

  • Any side effects

  • Your mental health and wellbeing

For children and young people, height and weight will be monitored regularly to check that treatment is not affecting normal growth and development.

These checks help your clinician decide whether your dose remains appropriate and whether any changes to your treatment are needed.

FAQs

When can I expect to notice a difference with dexamfetamine?

Dexamfetamine can begin working after your first dose, although it may take several weeks to experience its full benefits.

You may notice improvements in your concentration, focus and other ADHD symptoms within the first week of treatment.

Your clinician will usually start you on a low dose and gradually increase it over several weeks. During this time, they will monitor your symptoms and any side effects to find the dose that works best for you.

Dexamfetamine can reduce your appetite, which may lead to weight loss. Your clinician will monitor your weight during treatment and discuss any significant changes with you.

If you are still growing, dexamfetamine may also affect your growth. Your clinician will monitor your height and weight regularly.

Another common side effect is a dry mouth, which can increase the risk of tooth decay and gum problems over time. Maintaining good oral hygiene and attending regular dental check-ups can help.

Everyone responds differently to medication, so speak to your clinician if you have any concerns about changes to your body.

It is entirely your decision whether to tell family members or friends that you are taking dexamfetamine.

However, sharing this information with people you trust may help them understand your treatment, offer support and recognise any changes in your behaviour or potential side effects.

You do not need to tell everyone, but having someone you trust who understands your treatment can be helpful.

Dexamfetamine is a stimulant and can sometimes make it more difficult to fall asleep, particularly if you take it later in the day.

Your clinician will advise you on the most appropriate times to take your medication. Taking your doses earlier in the day may help reduce sleep difficulties.

However, some people find that better management of their ADHD symptoms actually improves their sleep.

If you experience ongoing sleep problems, speak to your clinician before changing your dose or the time you take your medication.

You should not drink alcohol while taking dexamfetamine.

Alcohol can increase the risk of side effects and may affect your judgement, coordination and ability to recognise how much alcohol you have consumed.

Combining dexamfetamine with recreational drugs, particularly stimulants such as cocaine, ecstasy or other amphetamines, can be dangerous and place additional strain on your heart and blood vessels.

Other recreational drugs may also cause serious interactions.

Speak to your clinician if you have any questions or concerns about alcohol or recreational drug use while taking your medication.

Some medicines can interact with dexamfetamine, including certain antidepressants, painkillers, migraine treatments, cold and flu remedies, and herbal supplements.

Taking dexamfetamine with certain medicines can increase the risk of serotonin syndrome, a potentially serious reaction.

Dexamfetamine must not be taken alongside monoamine oxidase inhibitors (MAOIs), or within 14 days of taking one.

Always tell your clinician about any prescription medicines, over-the-counter treatments or supplements you are taking.

Check with your clinician or pharmacist before starting any new medication.

For further information, please refer to the Other medicines and Serotonin syndrome sections above.

Some dexamfetamine tablets contain ingredients such as lactose or isomalt, which may be unsuitable for people with certain food intolerances.

Liquid formulations may also contain preservatives or other ingredients that could cause an allergic reaction.

If you have any allergies, food intolerances or dietary requirements, including avoiding animal-derived ingredients, speak to your pharmacist before taking your medication.

Your pharmacist can check the ingredients in your prescribed formulation and advise you on suitable alternatives if necessary.

Dexamfetamine can sometimes cause dizziness, drowsiness, blurred vision or changes in concentration, particularly when you first start taking it or when your dose changes.

Avoid driving until you understand how the medication affects you. You must not drive if your ability to drive safely is impaired.

Most people can continue driving normally once they are established on their medication.

You must inform the DVLA if your ADHD or medication affects your ability to drive safely.

As dexamfetamine is a controlled medication, it is also advisable to keep evidence of your prescription, such as a repeat prescription slip or a letter from your clinician.

Dexamfetamine may also produce a positive result on a roadside drug screening test. If you are driving while taking prescribed dexamfetamine, it is advisable to carry evidence of your prescription and ensure that you are taking your medication exactly as directed.

If you are pregnant, planning to become pregnant or breastfeeding, speak to your clinician about your medication.

Dexamfetamine is not generally recommended during pregnancy or breastfeeding unless your clinician determines that the benefits of treatment outweigh the potential risks.

Studies involving amphetamine medicines have suggested a possible increased risk of pre-eclampsia and premature birth. Babies exposed during pregnancy may also experience withdrawal symptoms after birth.

Dexamfetamine can pass into breast milk and may affect your baby.

If you could become pregnant, discuss contraception and pregnancy planning with your clinician.

If you become pregnant while taking dexamfetamine, contact your clinician as soon as possible rather than stopping your medication without medical advice.

Please refer to the Pregnancy and breastfeeding section above for further information.

Dexamfetamine can sometimes affect your sex life. Possible side effects include a reduced sex drive, difficulty achieving or maintaining an erection, or changes in sexual satisfaction.

These effects may improve as your body adjusts to the medication. Some people also find that better management of their ADHD symptoms has a positive effect on their relationships and sex life.

There is currently no clear evidence that dexamfetamine affects fertility.

If you experience persistent sexual side effects or are planning to have a baby, speak to your clinician for advice.

Most people can continue participating in sports and physical activities while taking dexamfetamine.

However, the medication can sometimes cause dizziness, blurred vision or changes in heart rate and blood pressure. Pay attention to how you feel, particularly when starting treatment or adjusting your dose.

Dexamfetamine is also included on the World Anti-Doping Agency’s list of substances prohibited during competition.

If you compete in a sport that follows anti-doping regulations, you may need a Therapeutic Use Exemption (TUE) to continue taking your prescribed medication.

Speak to your clinician and your sport’s governing body about the relevant requirements before competing. Do not stop taking your medication without medical advice.

Dexamfetamine may help improve concentration, focus and the ability to manage tasks, which can be beneficial when studying or taking exams.

However, when you first start treatment, you may experience side effects such as tiredness, dizziness or blurred vision while your body adjusts to the medication.

If you have important exams approaching, speak to your clinician about the best time to start treatment or make any changes to your dose.

Once you are established on your medication, you should generally be able to study and take exams as normal.

Questions or concerns

If you are experiencing side effects, are unsure how to take your medication or have questions about another medicine, contact the HG Mind Works clinical team before making changes to your treatment.

Speak to the clinical team