Table 1.

Main classes of mood stabiliser (and alternatives to valproate in the treatment of bipolar disorder), mechanisms of action and side effects (not including foetal or maternal risks). Compiled from various sources [10, 33, 34, 91–100]

Class	Medication name	Proposed mechanism(s) of action	Side effects
Mineral	Lithium	Enhances serotonergic neuron activity, inhibits pAp-phosphatase enzyme, interacts with nitric oxide signalling activity	Common: GI upset, fine tremor, polyuria, polydipsia, metallic taste in mouth, ankle oedema, weight gain. Chronic: renal toxicity, hypothyroidism.
Anti-epileptics	Sodium valproate	GABA potentiation, blocks voltage gated sodium channels, epigenetically inhibits histone deacetylase	Common: GI upset, hyperammonaemia (causing nausea), weight gain, tremor, hair loss with curly regrowth. In women: polycystic ovarian syndrome, hyperandrogenism. Rare: fulminant liver failure.
	Lamotrigine	GABA potentiation, suppresses glutamate release, inhibits serotonin reuptake	Common: tremors, dizziness, tiredness, loss of co-ordination, menstrual disturbance, dry mouth, sleep problems.
	Carbamazepine	Blocks voltage gated sodium channels	Common: dizziness, diplopia, drowsiness, ataxia, nausea, headaches, dry mouth, oedema, hyponatraemia, erythematous rash, sexual dysfunction. Rare: agranulocytosis.
Atypical antipsychotics	Risperidone	Dopaminergic (D1–5) receptor antagonist, serotonergic (5-HT2A/C) receptor antagonist	Common: sexual dysfunction (hyperprolactinaemia). Long term: movement disorders (e.g. tardive dyskinesia, akathisia, parkinsonism), increased risk of cardiovascular disease. Rare: neuroleptic malignant syndrome
	Olanzapine
	Quetiapine
	Aripiprazole	Dopaminergic (D2) and serotonergic (5-HT1A) receptor partial agonist	Common: weight gain, headache, agitation, insomnia, gastrointestinal effects, disinhibition.