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 gain is not a known side effect of lovastatin (see Mevacor and Weight Gain). Keep in mind that if you experience unexplained muscle pain, tenderness, or weakness (especially if you also have a fever or feel ill), it is important to contact your healthcare provider right away.