I am on Accutane and it says you are not allowed to drink alchohol. What about just a few drinks on occasion?

Increases risk. It's important to avoid drinking alcohol while on this drug because it decreases the risk of liver toxicity. Accutane also makes you feel dehydrated which alcohol also exacerbates. If you do drink it's against the doctor's advice. It's a known risk so why take a chance. You won't be on the drug forever, just play it safe while on the drug.
Things to ponder. Alcohol is a toxic substance that is de-toxified by the liver. Accutane is known on occasion to produce altered liver enzymes as a sign of irritation and these are routinely followed while on the drug. Rare cases of liver failure have occurred on this drug. The issue is how risky you want to play life. While you are on the drug, drinking increases your risk of liver damage , even in small amounts.