Golden seal is a North American herb people take for temporary digestive complaints and to calm irritated mucous membranes. Its main active part is berberine, which has antimicrobial and anti-inflammatory effects. The evidence from human studies is still thin.
You can find it as a capsule or powder. Most people take it with meals for short term stomach upset or use it as a gargle for minor throat soreness.
Never give golden seal to children. It carries a risk of kernicterus. Pregnant and nursing women should avoid it too. The herb can interfere with liver metabolism, so it interacts with drugs like warfarin, statins, and diabetes medications. It might also reduce blood sugar or blood pressure. Do not use it for long periods without a practitioner’s guidance.