A prescription is needed for these medicines. All medicines have some side effects, but not all people get them. Some people have different side effects than others. Most side effects happen in the first few hours of treatment and gradually go away. The best way to prevent constipation is to drink lots of water, juice, and other liquids, and to eat more fruits and vegetables.
Exercise also helps to prevent constipation.
Your doctor or nurse may also be able to give you a stool softener or a laxative. Nausea and vomiting. When this happens, it usually only lasts for the first day or two after starting a medicine. Tell your doctor or nurse about any nausea or vomiting. They can give you medicine to stop these side effects.