Serotonergic presynaptic nerve Serotonin

This is a 5-HT1 agonist (inhibiting the release of serotonin from presynaptic nerve terminals). Hence, even though it suppresses central serotonergic transmission (opposite to the effect of sertraline), there is an increased risk of central nervous system toxicity. Thus, the combined use of sertraline and sumatriptan is not usually recommended. 

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