Magnesium Sulfate

IV treatment of hypomagnesemia; tetany/grass staggers in horses; laxative/cathartic for impaction colic; tocolytic; topical Epsom salt soaks for hoof abscesses. Inorganic salt providing magnesium (Mg2+) and sulfate. Mechanism: Mg2+ is essential cofactor for >300 enzymatic reactions; inhibits neuromuscular transmission (calcium antagonist at NMJ → muscle relaxation); reduces uterine contractility (tocolysis); high oral doses draw water into colon (osmotic cathartic); topical (Epsom salts) draws edema fluid from hooves. IV infusion must be slow. Key information IV: administer slowly — rapid infusion causes respiratory depression and cardiac arrest. Monitor deep tendon reflexes and respiratory rate. Antidote: calcium gluconate. Store at room temperature. Cathartic/laxative (oral) — monitor electrolytes.

IV: dilute (maximum 20% for IV use); administer slowly via CRI with ECG monitoring. Antidote (calcium gluconate IV) must be available. Oral cathartic: dissolve in water and administer orally. Topical (Epsom salts): dissolve in warm water; soak affected area or apply as poultice. Store at room temperature; protect from light. If a dose is missed This medication is administered by a veterinarian or veterinary staff in a clinical setting. Missed doses are managed by your veterinary team — contact your veterinarian to reschedule.

IV: hypotension, respiratory depression, neuromuscular blockade, cardiac arrest (overdose/rapid infusion — monitor calcium as antidote). Oral: diarrhea, dehydration (osmotic cathartic). Oral high dose in horses: abdominal cramping. Hypermagnesemia with impaired renal function.

For animals IV: administer slowly with ECG and respiratory monitoring — rapid infusion causes neuromuscular blockade, respiratory arrest, cardiac arrest. Antidote: calcium gluconate IV. Oral cathartic: ensure adequate hydration. Reduce dose or extend interval in renal impairment. — use with caution (impaired Mg2+ excretion). For people handling this medication Wash hands thoroughly with soap and water after handling. Avoid contact with eyes; if contact occurs, flush with water for 15 minutes and seek medical attention. Keep out of reach of children. If accidental ingestion occurs, contact Poison Control (1-800-222-1222). Generally safe to handle. Wash hands thoroughly with soap and water after handling. Topical Epsom salt: safe for skin contact in dilute form.

Contact your veterinarian immediately. Magnesium overdose causes respiratory depression, cardiac arrest, and loss of deep tendon reflexes. Antidote: calcium gluconate by veterinary staff.