The most harmful drug when used with alcohol would likely be another depressant substance, such as benzodiazepines (e.g. Valium, Xanax) or opioids (e.g. heroin, fentanyl). Combining alcohol with these substances can lead to dangerous levels of central nervous system depression, respiratory depression, and increased risk of overdose. This combination can also increase the likelihood of accidents, falls, and other harmful consequences. It's important to avoid mixing alcohol with other depressant drugs to minimize the risks to your health and safety.
