Intrusive thought
Antidepressants which have been shown to be effective in treating OCD include fluvoxamine (trade name Luvox), fluoxetine (Prozac), sertraline (Zoloft), paroxetine (Paxil), citalopram (Celexa), and clomipramine (Anafranil). Although SSRIs are known to be effective for OCD in general, there have been fewer studies on their effectiveness for intrusive thoughts. A retrospective chart review of patients with sexual symptoms treated with SSRIs showed the greatest improvement was in those with intrusive sexual obsessions typical of OCD. A study of ten patients with religious or blasphemous obsessions found that most patients responded to treatment with fluoxetine or clomipramine. Women with postpartum depression often have anxiety as well, and may need lower starting doses of SSRIs; they may not respond fully to the medication, and may benefit from adding cognitive behavioral or response prevention therapy.
Besipirdine
Besipirdine was originally suggested as a treatment for OCD due to its effects on the adrenergic and serotonergic systems. "In vitro" studies of besipirdine indicated its potency in inhibiting serotonin reuptake in addition to norepinephrine reuptake. "In vivo", besipirdine showed efficacy in reducing schedule-induced polydipsia (SIP) in rats. The drug's anticonvulsant properties ultimately led Hoechst AG to pursue it as a treatment for Alzheimer's disease.
After its discontinuation in the mid-90's, besipirdine was re-evaluated as an oral treatment for Over Active Bladder (OAB) and is currently undergoing Phase III clinical trials, under UroGene. Interest in besipirdine as a treatment for OAB was piqued by its known effects on the adrenergic system. In isolated studies, besipirdine showed greater potency than duloxetine on bladder capacity, micturition volume, intercontraction interval, and an increase in striated sphincter EMG activity.