Possible Interaction: Citalopram and Tryptophan

“CONCLUSIONS Our findings support the hypothesis that ac te citalopram ad ministration increases try ptophan (b y inhibiting TDO activity) availability for 5-HT synthesis and activates serotonergic neurotransmission in limbic brain areas in rats exposed to FST paradigm.”

“Although TRP could be a useful strategy to improve the antidepressant effect of citalopram ( Cervo et al. 2005 ), particularly in subjects with low 5‐HT synthesis, the contribution of serotonergic and non‐serotonergic mechanisms to TRP’s effect remains to be elucidated.”

“Pretreatment with tryptophan raised 5-HTP accumulation and reinstated the antidepressant-like effect of citalopram in DBA/2J and BALB/c mice, whereas pharmacological inhibition of 5-HT synthesis prevented the effect of citalopram in C57BL/6J and 129/Sv mice.”

“ Citalopram increased tryptophan and tyrosine amounts, and decreased the 5-HT, 5-hydroxy-indoleacetic acid, kynurenine, and dopamine amounts in the brain.”