Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Nitroglycerin rectal can cause severe headaches, which may occur each time you use the medication. Your doctor may recommend treating fever and pain with an aspirin free pain reliever such as acetaminophen (Tylenol). Follow the label directions or your doctor's instructions about how much of this medicine to use.
Less serious side effects may include:
- dizziness; or
- mild headache.
This is not a complete list of side effects and others may occur.