3.3.6 Non psychotropic drugs with adverse actions on mental state

Deciding whether a drug is the cause

• Timing is the first clue, so date every new drug, dose change and withdrawal, including inhalers, patches, over-the-counter products and anabolic steroids.

• A delay of weeks does not exclude a drug cause, and stopping a drug can cause symptoms as well as starting one.

• Improvement on withdrawal and recurrence on accidental re-exposure both support causality.

• Exclude infection, hypoxia, electrolyte disturbance and the underlying disease before blaming the drug.

Corticosteroids

• Systemic corticosteroids can cause insomnia, mania, mixed states, psychosis, depression, delirium and suicidal thinking, often within days to two weeks of starting.

• Risk rises with dose: about 1 to 2% below 40 mg prednisolone daily, approaching 20% above 80 mg.

• Mania tends to come early, while depression comes with longer treatment or during tapering.

• Steroid-induced mania can occur without any psychiatric history.

Anabolic-androgenic steroids

• High-dose anabolic-androgenic steroids cause hypomanic symptoms, irritability, elevated or unstable mood, aggression and disinhibition while androgen levels are supraphysiological.

• Growth hormone does not cause this picture, because it has no androgenic action.

• Withdrawal can cause prolonged hypogonadism, fatigue, low libido and depression with suicide risk.

• They are Class C drugs in Schedule 4 Part II of the Misuse of Drugs Regulations 2001: possessing them in medicinal form for personal use is not an offence, but supplying or manufacturing them is.

Other hormonal and immune drugs

Dopamine agonists

• Ropinirole and pramipexole, used for restless legs syndrome, can cause impulse control disorders: gambling, compulsive shopping, hypersexuality and binge eating.

• These behaviours are thought to arise from action on D3 receptors in the ventral striatum, and patients should be asked about them directly.

• Dopaminergic drugs can also cause confusion, hallucinations and psychosis.

• Stopping an agonist abruptly can cause anxiety, pain, sweating and craving.

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Anticholinergic burden

• Central muscarinic blockade impairs attention and learning and can cause delirium, especially in older people and those with dementia.

• Oxybutynin, an antimuscarinic for urge incontinence, is a lipophilic tertiary amine, so it crosses the blood-brain barrier and adds to anticholinergic burden.

• The National Institute for Health and Care Excellence (NICE) advises against immediate-release oxybutynin in frail older women.

• Other contributors include hyoscine, sedating antihistamines, procyclidine, tricyclics and antipsychotics.

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Sympathomimetic drugs

• Beta-2 agonist inhalers such as salbutamol and decongestants raise adrenergic tone and cause anxiety, tremor and palpitations.

• Decongestants also cause insomnia and agitation, and occasionally psychosis.

• Central alpha-2 agonists and beta-blockers do the opposite: they lower adrenergic tone.

• Exclude hypoxia or uncontrolled asthma when symptoms look like panic.

Antimicrobials and antiepileptics