The most common side effects of saw palmetto occur in the stomach or intestines, and include constipation, gas, diarrhea and vomiting. Other possible side effects include indigestion, heartburn, nausea and stomach pain. Eating food with saw palmetto may reduce side effects related to the stomach and intestines, states Mayo Clinic.
Other possible side effects of saw palmetto include yellowing of the skin, breathing difficulties and other respiratory issues, liver inflammation or damage, and an abnormal heartbeat. Some people may experience depression, difficulty sleeping, muscle pain or headache. Additional potential side effects include chest pain; dizziness; shifts in blood pressure; and heart failure, attack or disease, according to Mayo Clinic.
Saw palmetto may cause impotence or erectile dysfunction in some men. Other possible side effects include breast enlargement or tenderness, urinary or genital issues, an inflamed pancreas, and skeletal muscle breakdown. Some people may experience symptoms that are similar to the flu, shifts in blood chemistry, fatigue and hot flashes, states Mayo Clinic.
People who have high blood pressure or who are taking medicines or supplements related to blood pressure should speak to a health care professional before using saw palmetto. Children and pregnant or nursing women should not use saw palmetto. Other conditions that may be complicated by saw palmetto include liver disorders, conditions related to hormones, stomach disorders and imminent surgery, notes Mayo Clinic.