Tweet. There are no known adverse reactions between Plavix (Clopidogrel) and eating grapefruit, or drinking grapefruit juice. Furthermore, there is no sufficient evidence that illustrates grapefruit juice, or the fruit itself would interfere with the effectiveness of Plavix.
Other, more minor side effects include constipation, headache, dry mouth and insomnia (because the chemicals in these drugs also influence sleep patterns). Herbal diet pills, even though they're all natural, can have potentially dangerous side effects depending upon their ingredients.
Weight-Loss Success. Weight loss was one of the most common side effects of Topamax, occurring in between 11 and 26 percent of patients taking the drug. According to Ortho-McNeil's Topamax website, some patients lose weight while taking Topamax, and the amount of weight loss varies according to the dosage taken.