Whenever I've tried to drink alcohol on opiate withdrawal, it makes everything worse. Alcohol alone can sometimes cause restless limbs, so when I would drink during withdrawal it made the restlessness that much worse. It also increased the shitty body feeling, and made my emotions more unstable, and also lowered my inhibitions so it made it harder to resist getting more opiates. Plus then the hangover in the morning made the withdrawal worse. Highly not recommended.