From: Sodium valproate in pregnancy: what are the risks and should we use a shared decision-making approach?
Proposed mechanism(s) of action
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.
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.
GABA potentiation, suppresses glutamate release, inhibits serotonin reuptake
Common: tremors, dizziness, tiredness, loss of co-ordination, menstrual disturbance, dry mouth, sleep problems.
Blocks voltage gated sodium channels
Common: dizziness, diplopia, drowsiness, ataxia, nausea, headaches, dry mouth, oedema, hyponatraemia, erythematous rash, sexual dysfunction.
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
Dopaminergic (D2) and serotonergic (5-HT1A) receptor partial agonist
Common: weight gain, headache, agitation, insomnia, gastrointestinal effects, disinhibition.