3 Clinical psychopharmacology3.4 Therapeutics

3.4.1.2.1 Specific psychiatric diagnoses

Creator: Resident Doctor Committee
Published: 2026-10-14T21:05:16.259Z

3 min read2 figures

Written by Resident Doctor Committee · Published 14 October 2026

Confirming the diagnosis first

A drug's benefit in one disorder does not transfer automatically to a similar symptom in another. Match the drug to the diagnosis and its severity.

Ask about previous mania or hypomania before treating depression, because antidepressants can worsen activation in bipolar disorder.
Tell anxiety disorders apart from post-traumatic stress disorder (PTSD) and obsessive-compulsive disorder (OCD).
Look for substance, medical and neurological causes, especially with late onset, fluctuating consciousness, focal signs or rapid change.

First-episode psychosis is treated first with a low-dose oral antipsychotic chosen with the patient according to side effects, such as low-dose oral aripiprazole.

Situation	Treatment
Long-term treatment	Lithium is first-line in National Institute for Health and Care Excellence (NICE) guidance: it prevents manic and depressive relapse and lowers suicide risk
Mixed affective episode	NICE manages it as mania, with an antimanic agent; quetiapine is first-line
Mania in pregnancy	An antipsychotic first, such as haloperidol, which has a long reproductive safety record and little effect on weight or glucose
Moderate depression, no antimanic drug	NICE recommends quetiapine alone, or olanzapine with fluoxetine
Moderate or severe depression after first-line options fail or are declined	Lamotrigine is a NICE-listed option

Lamotrigine prevents depressive relapse without level monitoring, but NICE says not to use it for mania.
Slow titration of lamotrigine over weeks lowers the risk of serious rash, including Stevens-Johnson syndrome.
Selective serotonin reuptake inhibitors (SSRIs) switch people into mania less often than tricyclics and serotonin-noradrenaline reuptake inhibitors, so an SSRI is the antidepressant added to an antimanic agent.
Avoid antidepressant monotherapy where mania is a risk.

Partial response to a well-tolerated antidepressant after a failed switch calls for augmentation, and aripiprazole augments with low risk of weight gain and hyperglycaemia.
In OCD, SSRIs are the first-line class, given at high doses over a 12-week trial, and clomipramine also has established efficacy.
Social anxiety disorder is treated first with individual disorder-specific cognitive behavioural therapy, with an SSRI as the drug option.
Pregabalin has randomised placebo-controlled evidence in social anxiety disorder, but NICE does not recommend it.

Trauma-focused psychological therapy is preferred, and drugs are for adults who choose them.

Drug	Point to remember
Sertraline	The example SSRI in NICE's 2018 guideline for an adult who prefers drug treatment
Venlafaxine	The only non-SSRI that NICE offers
Risperidone	For disabling symptoms (severe hyperarousal, psychotic features) unresponsive to other treatment, added to psychological therapy and started by a specialist
Prazosin	An alpha-1 blocker given at bedtime for trauma nightmares, titrated slowly because of first-dose postural hypotension; NICE makes no recommendation and trial evidence is mixed

Only sertraline and paroxetine hold a UK licence for PTSD, because neither a NICE recommendation nor membership of the SSRI class confers one.

Presentation	Treatment
Adult attention deficit hyperactivity disorder (ADHD)	Methylphenidate or lisdexamfetamine first; atomoxetine next if neither helps or is tolerated after separate six-week trials
Akathisia not helped by dose reduction	Low-dose propranolol, a lipophilic beta-blocker; low-dose mirtazapine or cyproheptadine are alternatives
Severe self-injury in autism with intellectual disability, persisting after two adequate antipsychotic trials	Naltrexone, an opioid antagonist