Tegrital 200 Tablet (Carbamazepine) is generally safe and effective for long-term seizure control, but taking it for 21 years without any medical follow-up is not advisable. You should consult a doctor or neurologist for a detailed evaluation to determine whether the current dose is still appropriate or if a change in medication is needed and to check for any long-term side effects. Prolonged use requires regular monitoring of liver function, blood cell counts, and bone health. Do not stop or change this medication without medical supervision.