<p>Fluoxetine has been shown to selectively inhibit the reuptake of serotonin at the presynaptic neuronal membrane which causes increased synaptic concentration of serotonin in the CNS. This result in numerous functional changes associated with enhanced serotonergic neurotransmission. Fluoxetine appears to have no effect on the reuptake of norepinephrine and dopamine and does not exhibit anticholinergic, antihistaminic or &alpha;1 adrenergic blocking activity at usual therapeutic doses.</p>