Combining alcohol with cannabis greatly increases a personu2019s level of impairment, which can then increase the risk of injury or death from accidents. Cannabis may also interact with certain prescription medications. You should avoid cannabis if you are taking any medications that slow down the central nervous system such as sleeping pills, some pain medications such as opioids, and some medications used to treat seizures or anxiety disorders, such as benzodiazepines. It should also be avoided by those taking anti-psychotic medications like clozapine or olanzapine. Cannabis use may also result in unintended side effects if you are taking certain anti-depressants, some allergy or cold medications, stomach acid inhibitors, certain antibiotic and antifungal medications, or certain antiretroviral medications used to treat HIV/AIDS.