Hello marie evie,   Even if you boyfriend continues to take the street drugs, he should stay on his medication.  However, taking street drugs is a no-win situation and chances are a person won't recover if he continues to take illegal drugs. Street drugs could actually CAUSE paranoia and other symptoms. This is called "MICA": a mental illness-chemical abuse combination, and there are professionals trained to treat people with this dual diagnosis.  The two illnesses have to be treated together, by professionals who are well versed in this one-two combo. Getting him into treatment is another story. I wish you all the best.   Regards, Chri