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.
It is not entirely clear why Wellbutrin can cause weight loss. Wellbutrin can often cause a loss of appetite, nausea, and vomiting -- all of which may contribute to weight loss. Often, these side effects go away with time.