Yes it is bad advice. Do not take 5HTP the day of your MDMA ingestion or while on MDMA. It dulls the effects. Yes opiates also dull MDMA effects, I've personally experienced this with myself. Opiate half life has a lot to do with dulled effects. I took 400mg of MDMA the evening one the same day I took a shot of Opana in the morning and had little to no effects, I went to bed and woke up at 5am and dosed 150mg of MDMA had an amazing experience. nomad bloodbath