One of the side effects of taking cyproheptadine is weight gain, according to RXList. Other common side effects include dizziness, drowsiness, loss of coordination, blurred vision, constipation, upset stomach, increased appetite, dry mouth, nose or throat and thickening of mucus in the throat or nose.
Cyproheptadine is classified as an antihistamine and is used for treating symptoms of allergies, including runny nose, watery and itchy eyes and sneezing. It is clinically known as cyproheptadine hydrochloride, and it is available in generic format.
Dosing for this drug varies based on whether the patient is an adult or a child. Adults take doses ranging from 4 to 20 milligrams daily, states RXList. Pediatric patients are dosed based on their body weight.
Cyproheptadine interacts negatively with many other medications, including drugs used to treat Parkinson's disease, antispasmodic drugs, anticholinergic drugs and muscle relaxers. The drug also interacts with antiseizure drugs, narcotic pain medicines, sleeping or anxiety medication, and psychiatric medicines.
An allergic reaction to cyproheptadine should be evaluated by a medical doctor right away. Some signs of a serious allergic reaction include ringing in the ears, feeling faint, easy bruising, confusion, unusual behavior or thoughts, seizures and easy bleeding. Other signs to watch for include fast heartbeat, yellowing of the skin and lack of urination.