All the drugs are used as a prophylaxis in pt with migraine except?

All the given drugs are used as prophylaxis of migraine . Pharmacological Treatment of Migraine (2) Drug(s) Comments : * Used for many years but no data suppo use Barbiturates * Associated with a variety of adverse events (especially butalbital) * Patients regularly using barbiturates be evaluated and provided with an alternative therapy * Use should be limited in treatment of migraine Opioids * Sho-term use may be appropriate in some patients * Use must be vigilantly monitored Triptans * Rapid onset of action * High efficacy * Favourable side effect profile * Long history of use and low cost, but many possible associated adverse events Ergot alkaloids * Largely been replaced triptans Complex pharmacology and potential drug interactions (notably triptans) ref : kd tripathi 8th ed