The side effects of nicotine gum include vomiting, mouth blisters, rash, weakness and dizziness, as stated by MedlinePlus. Others include jaw problems, irregular heartbeat, nausea and diarrhea. A person should stop using the medicine when these symptoms appear.
Nicotine gum helps to quit smoking, and it works by ensuring low levels of nicotine, which minimizes withdrawal symptoms. Patients who are allergic to any nicotine gum ingredient and those who suffered a recent heart attack should not use this drug, notes Drugs.com. Taking alcohol while using the gum worsens the side effects. Pregnant women should contact a doctor before using nicotine gum. In addition, a patient should not chew more than 24 pieces in a day unless advised by a doctor.