Paroxetine

Paroxetine is a selective 5HT uptake blocker, with sleep slightly improved by administration in the morning.

Licensed indications in the UK:

• depressive illness
• obsessive-compulsive disorder
• panic disorder
• social phobia
• post-traumatic stress disorder
• generalised anxiety disorder

The usual initial dosage is 20 mg mane; the dose-response curve plateaus at 20 mg although doses may be given up to 50 mg in the treatment of depressive illness, panic disorder and social phobia (a maximum dose of 60 mg per day is licensed in the UK for the treatment of obsessive compulsive disorder).

Use of paroxetine in patients under 18 years of age:

Paroxetine is now contraindicated in patients with major depressive disorders under 18 years of age (1)

A recently completed programme of clinical trials in children and adolescents under 18 years of age failed to demonstrate efficacy in Major Depressive disorder and there was a doubling of the rate of reporting of adverse events in the paroxetine group compared to placebo, including: reduced appetite, tremor, sweating, hostility, hyperkinesia, agitation, emotional lability (including crying, mood fluctuations, self-harm, suicidal thoughts and attempted suicide)

Note - if an antidepressant is prescribed to a child or young person, it should be fluoxetine, and this should not be prescribed except after assessment and diagnosis by a child and adolescent psychiatrist.(2)

Withdrawal Symptoms Associated with Paroxetine (3)

Stopping SSRIs - including paroxetine - leads to a withdrawal or discontinuation syndrome. It is now recognised that this syndrome can sometimes cause severely distressing and debilitating symptoms. These include:

• agitation
• insomnia
• unsteadiness
• marked sweating
• nausea and diarrhoea
• irritability, anxiety or confusion
• lowering of mood.
• suicidal ideation.
• myalgia and tremors.
• malaise.

These symptoms typically occur within days of stopping the SSRI, although they may occur earlier or later depending on the half-life of the drug.

The summary of product characteristics should be consulted before prescribing this drug.

Reference:

1. Letter from GlaxoSmithKline Re: Seroxat (paroxetine hydrochloride) - contraindication in children under 18 for the treatment of major depressive disorder (SRX/MLP/03/08454/1 - June 2003)
2. NICE. Depression in children and young people: identification and management. NICE guideline NG134. Published June 2019
3. Palmer EG et al. Withdrawing from SSRI antidepressants: advice for primary care. Br J Gen Pract. 2023 Feb 23;73(728):138-140.