Welcome to Healthcare magic . Thank you for posting your query. I can understand your concern for this man you are dating. Alcohol and drugs are indeed dangerous. 1. Alcohol can cause harm to almost all systems . It can cause gastritis , cirrhosis of liver , oral and stomach cancer , pancreatitis , pancreatic cancer, heart dysfunction(dilated cardiomyopathy) . It can cause psychiatric disorders like anxiety , panic disorders and even brain atrophy and many more. 2. Cocaine is a powerfully addictive stimulant drug made from the leaves of the coca plant.Cocaine affects the body in a variety of ways. It constricts blood vessels, dilates pupils, and increases body temperature, heart rate, and blood pressure. It can also cause headaches and gastrointestinal complications such as abdominal pain and nausea. Because cocaine tends to decrease appetite, chronic users can become malnourished as well. Most seriously, people who use cocaine can suffer heart attacks or strokes, which may cause sudden death. Cocaine-related deaths are often a result of the heart stopping (cardiac arrest) followed by an arrest of breathing. Hope this helps. Hopefully you will be able to inform him about the adverse effects of alcohol and drugs. Post any other question. We are ready to help.