With the following exceptions, most herbs and drugs can be safely mixed.

Here are the drug / vitamin / herb mixtures you should avoid:

• Never take long-acting Niacin if you take Statin-like drugs (lowers cholesterol). A combination of the two could cause excessive metabolic stress to the liver. Remember, long-acting Niacin in gram doses acts like a drug (don't worry if you're taking small doses of short-acing preparations).

• Do not take standard dosages of gingko biloba (120-240mg daily) if you're on Coumadine (thins blood). You can however, safely take multi-vitamin and mineral combinations with small amounts of Gingko in them (less than 40mg daily).

• If you're on Digoxin, take hawthorne berry only under a physician's guidance. This combo could cause your heart rate to slow down too much.

• If you're taking Digoxin with beta blockers, stay away from large doses of vitamin E (more than 800 IU) and magnesium (more than 600mg), as a combination of this mixture may cause an additional heart rate slowing.

• Never use Kava Kava or St. John's wort, natural supplements for depression, with anti-depression drugs like Prozac, Paxil or Zoloft. An overdose of serotonin, the brain's happy hormone, may occur, resulting in serotonin excess, which manifests itself as irritability, dry mouth and insomnia.

• Do not use the herbs valerian root or passion flower if you take tranquilizers like Valium or Xanax because this combination can make you drowsy.