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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
All of the following drugs acts by blocking calcium channels except
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The correct answer is  Dantrolene is a directly acting skeletal muscle relaxant. It is used for treating malignant hypehermia. It is available as an injection All others are calcium channel blockers used in HTN REF.Essentials of Pharmacology KD Tripathi 8th ed.