Thanks for your question. You are correct: 5-HTP is a precursor of serotonin (5-hydroxytryptamine) and boosts serotonin levels in the Central Nervous System (brain). Seroquel inhibits multiple neurotransmitter receptors in the brain, including serotonin types 1 and 2 (5-HT1A and 5-HT2), to effectively lower serotonin levels in order to exert the desired psychiatric response of this medication. Why were you prescribed the 5-HTP? It seems to counteract the effect of the Seroquel... and when you say your body is not receiving it well, what does that mean?