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Terms Of Use


Brand Name(s) : Prothiaden
Side Effects


Dosulepin should be used with caution in:

It should not be used in:

  • Children
  • Pregnant women or women planning to become pregnant
  • Breast feeding women
  • Known hypersensitivity (allergy) to dosulepin or any of the other ingredients in the medicine
  • People with severe liver disease
  • People with hereditary blood disorders (porphyrias)
  • People who have recently had a heart attack
  • People with decreased heart function due to problems with its electrical activity (heart block)
  • People with an abnormal heart beat such as arrhythmias
  • People with mania
  • People who have taken a monoamine oxidase inhibitor (MAOI) for depression in the last two weeks.

Also see list of precautions and interactions


Do not store above 25°C.


What is it used for?

  • Dosulepin is used to treat depression.
  • It is a tricyclic antidepressant, sometimes known as a mood elevator.
  • It is used to relieve the symptoms of depression.
  • In general this drug is used to improve mood and behaviour in people with depressive illness, particularly in those with anxiety. Dosulepin is also useful in treating people with depression where sleeping difficulties and loss of appetite are predominant symptoms.
  • Benefits of being on this drug can include improved mood as assessed by various rating scales.

Listed below are the typical uses of dosulepin.

On occasion your doctor may prescribe this medicine to treat a condition not on the above list. Such conditions are listed below.


Dosulepin is available in tablet or capsule form.

How often do I take it?

  • Take this medication orally usually 2 to 3 times daily or as a single dose at night, preferably after food. Swallow the tablet or capsule with water.
  • Use this medication regularly in order to get the most benefit from it.
  • Remember to use it at the same time each day - unless specifically told otherwise by your doctor.
  • It may take between two to four weeks before you start to feel any benefit regarding your depressive symptoms, but it is important to keep taking your medicine. If your depression is getting worse and you are having any thoughts of harming or killing yourself, it is very important to see your doctor. This is because some people may get worse in the first few weeks of treatment. It may take up to several weeks before the full benefit of this drug takes effect. The anti-anxiety action of this medicine may only take a few days before you notice an effect.
  • Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your age, gender, medical condition, response to therapy, and use of certain interacting medicines.

Do I need to avoid anything?

  • This medication may cause drowsiness. If you are affected you should avoid driving or operating machinery.
  • Alcohol intake should be avoided while taking this medication. Consult your doctor or pharmacist for more details.

When can I stop?

  • It is important to continue taking this medication even if you feel well, unless your doctor tells you to stop.
  • You must follow your doctor's instructions for stopping this medication as the dose may need to be lowered gradually. Withdrawal symptoms such as difficulty sleeping, being irritable and excessive sweating can occur if you suddenly stop taking this medication.


  • Dry mouth
  • Drowsiness
  • Blurred vision
  • Constipation
  • Nausea (feeling sick)
  • Difficulty passing urine
  • Feeling faint or dizzy on changing position (due to low blood pressure)
  • Rapid heart beat
  • Abnormal heart beat
  • Sweating
  • Tremor
  • Skin rash
  • Confusion or delirium (particularly the elderly)
  • Headache
  • Sexual problems
  • Changes in behaviour
  • Increased appetite
  • Weight gain
  • Changes in taste
  • Fits (convulsions)
  • Enlarged breasts
  • Breast milk leaking from nipples
  • Itchy rash
  • Increased sensitivity to sunlight
  • Abnormal laboratory test results - decreased blood sodium, increased blood sugar and changes in white blood cell and platelet count

If any of these persist or you consider them severe then inform your doctor or pharmacist.

Tell your doctor immediately and stop taking dosulepin if you develop any of the following symptoms:

  • Fever, loss of consciousness, yellowing of the skin (jaundice)
  • Skin rash, difficulty swallowing (see serious allergic reaction)

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.


Before taking dosulepin, tell your doctor or pharmacist if you are allergic to it; or to other tricyclic antidepressants; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have:

  • Known hypersensitivity (allergy) to dosulepin or any of the other ingredients in the medicine
  • Severe liver disease
  • Recently had a heart attack
  • Decreased heart function due to problems with its electrical activity (heart block)
  • Abnormal heart beat such as arrhythmias
  • Mania

Before using this medication, tell your doctor or pharmacist your medical history, especially any of the following

  • Decreased liver function
  • Heart disease
  • Difficulty passing urine (urinary retention)
  • Enlarged prostate gland (prostatic hypertrophy)
  • History of glaucoma (increased pressure within the eye)
  • Epilepsy or risk factors for fits
  • Thyroid disease
  • Tumour of the adrenal gland (phaeochromocytoma)
  • Schizophrenia or other psychoses (mental illness with hallucinations, delusions and /or abnormal thoughts)
  • Hereditary blood disorders (porphyrias)

Before having surgery, tell your doctor or dentist that you are taking this medication.

Does alcohol intake affect this drug?

  • Alcohol intake is likely to add to the drowsiness experienced with dosulepin and should be avoided.

The elderly: dosulepin should be used with caution in the elderly as the risk of side effects, especially agitation, confusion and decreased blood pressure on changing position may be increased.

Pregnancy and breastfeeding - please ensure you read the detailed information below


The safety of dosulepin has not been established during pregnancy. The manufacturer therefore states that it is not recommended if you are pregnant or are planning on becoming pregnant.

In particular
First trimester: Avoid use
Third trimester: Avoid use

Ask your doctor or pharmacist if you have any doubts or questions about this.
It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Dosulepin passes into breast milk. The manufacturer therefore states that it should not be taken if you are breastfeeding.
Ask your doctor or pharmacist if you have any doubts or questions about this.

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Before using this medicine, tell your prescriber of all the medicines you are taking including prescription medicines and medicines you have bought over the counter without a prescription. Tell your prescriber if you are taking vitamins or complementary remedies such as herbal products, as these can also interact with medicines.

If you are taking more than one medicine, these may interact with each other. Your prescriber may decide to use medicines which interact with each other if the benefit outweighs the risks. In these cases, the dose of your medicines may need to be adjusted or you may be monitored more closely.

The folloing medicines may interact with dosulepin:

  • Monoamine oxidase inhibitors (MAOIs) used to treat depression or within two weeks of stopping treatment (e.g. isocarboxazid, moclobemide and phenelzine)
  • Alcohol and medications which have an effect on breathing rate and sleepiness
    -Sedatives, hypnotics, anxiolytics (for sleeping troubles and anxiety, such as zopiclone, diazepam, nitrazepam)
    -Opioid analgesics (for pain, such as codeine, morphine, tramadol)
    -Sedating antihistamines (for allergies, such as chlorphenamine, hydroxyzine, promethazine)
  • Adrenaline, noradrenaline
  • General anaesthetics
  • Alpha blockers used to treat high blood pressure and enlarged prostate gland (such as clonidine, doxazosin, guanethidine and terazosin)
  • Antidepressants known as SSRI antidepressants, e.g. fluoxetine, paroxetine
  • Atomoxetine (used to treat attention deficit hyperactivity disorder - ADHD)
  • Calcium channel blockers such as diltiazem and verapamil (used to treat high blood pressure and angina)
  • Cimetidine (used to treat indigestion and heartburn)
  • Contraceptives containing oestrogen
  • Diuretics used to treat heart failure and high blood pressure such as furosemide
  • Electroconvulsive therapy (ECT)
  • Lithium (used to treat mental health problems)
  • Methylphenidate (used to treat attention deficit hyperactivity disorder - ADHD)
  • Moxifloxacin (an antibiotic)
  • Pentamidine (used to treat chest infections caused by the protozoa, Pneumocystis carinii)
  • Rasagiline and selegiline (MAO-B inhibitors used to treat Parkinson's disease)
  • Rifampicin (an antibiotic)
  • Ritonavir (used to treat HIV infection)
  • Thyroid hormones
  • Warfarin (used to prevent blood clotting)
  • Medicines used to treat abnormal heart beat (antiarrhythmics) such as amiodarone, disopyramide, flecainide, propafenone and sotalol
  • Medicines used to treat psychoses such as haloperidol, pimozide and thioridazine
  • Medicines used to treat epilepsy such as carbamazepine, phenobarbital, phenytoin and primidone
  • Medicines with an anticholinergic effect, including those for:
    -Irritable bowel syndrome (such as hyoscine)
    -Bladder weakness (such as flavoxate, oxybutynin and tolterodine)
    -Antihistamines used to treat allergies such as astemizole and terfenadine

This information does not contain all possible interactions. Therefore, tell your prescriber of all the products you are using before taking this medicine.

If you have a question or want to discuss anything about your medicine, speak to your local pharmacist.


Always take the dose recommended by your doctor. If you accidentally take too much, you should contact your doctor immediately.
This is very important as dosulepin is associated with a high death rate in overdose. The effects of the overdose occur within 4 to 6 hours.

An overdose of dosulepin may cause dry mouth, excitement, problems with coordination, drowsiness, loss of consciousness, respiratory or metabolic alkalosis, muscle twitching, convulsions, widely dilated pupils, tremor, rapid heart beats, abnormal heart beat, low blood pressure, slow and shallow breathing, visual hallucinations and delirium. You may also feel very cold and be unable to urinate or defecate due to a blocked intestine.

If you think you, or someone you care for, might have accidentally taken more than the recommended dose of dosulepin or intentional overdose is suspected, contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.


Take the missed dose as soon as you remember it. Take any remaining doses for that day at evenly spaced intervals. If you miss two or more doses in a row, contact your doctor for advice.

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Source: Selected from data included with permission and copyrighted by Boots UK Limited. This copyrighted material is sourced from a licensed data provider and is not for distribution, except as may be authorised by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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