Can Medications Increase Blood Alcohol Content If Alcohol Was Also Present In The System?

Hello. My brother recently had a drug overdose (OxyContin, muscle relaxer, anti inflammatory and anti depressant) he had a serotonin issue. They also found alcohol in his blood. Can chemical pills cause a BAC to rise? That’s what the drs are saying and I can’t find any info. I think he was drinking and overdosed after having ankle replacement surgery. He’s in the hospital now but no one is answering my question: can pills increase blood alcohol content? I know it’s silly but I need to know. Thank you