#9. Alli – Severe Gas
Alli is a weight loss medicine that treats you by preventing your body from absorbing anymore fat. This means that when you eat food with high volumes of fat, Alli will prevent your body from absorbing and subsequently digesting that fat. But a major side effect of Alli is suffering from extreme constipation and gas, and being in pain as a result of it. Feeling bloated as a side effect is one thing, but being in pain from it is certainly another.