BMA Concise Guide to Medicine & Drugs

Paroxetine

Brand name Seroxat

Used in the following combined preparations None

QUICK REFERENCE

Drug group Antidepressant drug

Overdose danger rating Low

Dependence rating Low

Prescription needed Yes

Available as generic Yes

GENERAL INFORMATION

Paroxetine is a selective serotonin re-uptake inhibitor (SSRI) antidepressant. It is used in the treatment of depression, and helps to control the anxiety that often accompanies it. It is also used to treat generalized anxiety disorder, social phobia, panic disorder, obsessive-compulsive disorders, and post-traumatic stress disorder. Paroxetine is sometimes given to treat severe premenstrual syndrome.

It is less likely than the older tricyclic antidepressants to cause anticholinergic side effects such as dry mouth, blurred vision, and difficulty in passing urine, and is much less dangerous in overdose.

The most common adverse effects include nausea, diarrhoea, insomnia, and sexual problems, such as lack of orgasm. Withdrawal symptoms can occur if the drug is not stopped gradually over at least four weeks.

INFORMATION FOR USERS

Your drug prescription is tailored for you. Do not alter dosage without checking with your doctor.

How taken/used Tablets, liquid.

Frequency and timing of doses Once daily, in the morning.

Dosage range 10–40mg daily.

Onset of effect Onset of therapeutic response, usually within 14 days; full antidepressant effect may not be felt for 6 weeks (or longer for anxiety disorders).

Duration of action Antidepressant effect may last for some time following prolonged use.

Diet advice None.

Storage Keep in original container at room temperature out of the reach of children.

Missed dose Take as soon as you remember.

Stopping the drug Do not stop the drug without consulting your doctor. Stopping abruptly can cause withdrawal symptoms.

Exceeding the dose An occasional unintentional extra dose is unlikely to be a cause for concern. Large doses may cause unusual drowsiness. Notify your doctor immediately.

POSSIBLE ADVERSE EFFECTS

Common adverse effects of paroxetine include nausea, diarrhoea, sweating, tremor, weakness, drowsiness, dizziness, insomnia, and sexual dysfunction in both sexes (lack of orgasm, male ejaculation problems). Rarely, nervousness, anxiety, and agitation occur. Discuss with your doctor if any of these effects are severe. If there are suicidal thoughts or suicide attempts, stop taking the drug and seek urgent medical help.

INTERACTIONS

General note Any drug that affects the breakdown of others in the liver may alter blood levels of paroxetine or vice versa.

Anticoagulants Paroxetine may increase the effects of these drugs.

Antipsychotics and tricyclic antidepressants Paroxetine may increase the levels and toxicity of these drugs.

Monoamine oxidase inhibitors (MAOIs) Paroxetine should not be taken during or within 14 days of MAOI treatment because serious reactions may occur.

Aspirin and non-steroidal anti-inflammatory drugs (NSAIDS) There is an increased risk of gastric bleeding when these drugs are used with paroxetine.

SPECIAL PRECAUTIONS

Be sure to tell your doctor if:

· You have long-term liver or kidney problems.

· You have heart problems or bleeding disorders.

· You have glaucoma.

· You have a history of mania, or a history or family history of epilepsy.

· You have had problems withdrawing from other antidepressants.

· You are taking other medicines.

Pregnancy Safety in pregnancy not established. Discuss with your doctor.

Breast-feeding The drug passes into the breast milk. Discuss with your doctor.

Infants and children Not generally recommended under 18 years.

Over 60 Increased likelihood of adverse effects. Reduced dose may be necessary.

Driving and hazardous work Avoid such activities until you have learned how paroxetine affects you because the drug can cause drowsiness.

Alcohol Avoid. Alcohol may increase the sedative effects of this drug.

PROLONGED USE

Withdrawal symptoms may occur if the drug is not stopped gradually over at least 4 weeks. Such symptoms include dizziness, electric shock sensations, anxiety, nausea, and insomnia. These rarely last for more than 1–2 weeks. There is also a small risk of suicidal thoughts and self-harm in children and adolescents, although the drug is rarely used for this age group.

Monitoring Any person experiencing drowsiness, confusion, muscle cramps, or seizures should be monitored for low sodium levels in the blood. Under-18s should be monitored for suicidal thoughts and self-harm.