Some drugs primarily affect one neurotransmitter or class of neurotransmitters for example prescription opioids and heroin produce effects that are similar to but more pronounced than those produced by the neurotransmitters endorphin and enkephalin increased analgesia decreased alertness and slowed respiration. Serotonin is a neurotransmitter that affects mood memory processing and cognition psychiatric medications frequently target serotonin in order to modify the levels of this neurotransmitter in the brain selective serotonin reuptake inhibitors ssris are a class of antidepressant medications that includes prozac and paxil. Serotonin is a neurotransmitter primarily associated with hallucinogenic drugs like mdma or ecstasy lsd psilopsybin mushrooms philosophers stones etc serotonin famously affects sexual desire and sleep during active drug use but upon cessation can cause significant disruptions in the normal healthy functioning of both. Do not use drugs for fun take drugs exactly as prescribed by a trustworthy doctor and do not fear necessary prescription drugs because of terrible side effects on this chart which by the way may be inapplicable or extremely rare in your case and have been considered by your doctor this chart provides a rough overview of some common recreational drugs this chart is an oversimplification