Some users report feeling agitated, having mood swings, or having high blood pressure. Severe skin reactions, allergic reactions, or mental symptoms, including despair or agitation, are uncommon but dangerous. Without a doctor's advice, using excessive dosages of medications like Modvigil 200 may put more stress on the heart and interfere with regular sleep cycles. Medical monitoring is crucial since the danger of drug interactions and dependency is low but conceivable.