One, alcohol intake increases the content of lactic acid in your body. Excessive build up of lactic acid in your body can lead to cramps or pain in your muscles. Two, alcohol leads to dehydration. Your body ends up falling short on electrolytes, and you tend to experience muscle pain or cramps.e are well aware about the fact that over intake of alcohol can cause severe side effects on the body. However, what could be the reason behind leg pain after drinking too much alcohol.