Some supplements lose their potency after time. Read the label and stick to the dosage. Exceeding the recommended dosage can be dangerous. Watch out for combining things with similar effects, such as two stimulants or two depressants. Consult with your doctor before mixing prescription drugs and herbal supplements.
Some supplements can counteract drugs' effects.
Others, when mixed with prescription drugs, can cause hazardous side effects. Notify your doctor if you are taking supplements. Some can interfere with lab tests and some should be discontinued before surgery. Herbal Research Foundation, Pharmaca Integrative Pharmacy, CU School of Pharmacy. The Daily Camera.