The early laboratory studies evaluated divalproex, an anticonvulsant which is used clinically as a mood stabilizer and to treat epilepsy and migraine headaches [39] buproprion, which is used clinically as an antidepressant and for smoking cessation; and nefazodone, an antidepressant that blocks post-synaptic 5HT-2a receptors and inhibits pre-synaptic 5HT and NE reuptake [40]. Bupropion is thought to exert its clinical effects by inhibiting reuptake of norepinephrine (NE) and dopamine (DA) and possibly by acting as a nicotine receptor antagonist [41]. Single doses of bupropion sustained-release (300 mg/day for 17 days) and divalproex (1500 mg/day for 29 days) actually worsened, rather than improved, some withdrawal symptoms and had no positive effects [42, 43]. A single dose of nefazodone (450 mg/day) decreased some, but not the majority, of cannabis withdrawal symptoms [44].
