Which among the following is an early sign of magnesium toxicity? NOT RELATED-MEDICINE: (A) Depression of deep tendon reflexes, (B) Respiratory depression, (C) Cardiac arrest, (D) Decreased urine output
Answer is A. Ref:Drug Facts and Comparisons 2010/127 *Knee jerk (patellar reflex) stas diminishing at plasma magnesium concentration of 4mEq/L and disappears at 10mEq/L, where respiratory paralysis is a potential hazard.