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Magnesium Sulfate

MgSO4, Epsom Salt(injectable)

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Sourced from published veterinary references. Awaiting credentialed clinical reviewer — our editorial process.

Drug Class

Emergency

Routes

IVIM

Indications

hypomagnesemiarefractory seizuresTorsades de pointes

Mechanism of Action

Essential electrolyte. Blocks neuromuscular transmission, stabilizes cardiac membranes, and causes smooth muscle relaxation. Cofactor for 300+ enzymes.

Side effects & warnings

Treatment for hypomagnesemia, torsades de pointes, and eclampsia. Slow IV infusion. Respiratory depression at high levels. Monitor ECG and reflexes. Antidote: calcium gluconate.

Species with Magnesium Sulfate dosing data (2 dose rules)

Cat (Domestic)Dog (Domestic)

Species references:All Cat (Domestic) drugsAll Dog (Domestic) drugs

Evidence levels across 2 dose rules

Moderate×2

Each ExoticRx dose rule is graded by the strength of its primary evidence — see the editorial process.

Backed by a published source

  • · Plumb's Veterinary Drug Handbook, 9th Ed

Constant rate infusion (CRI)

Magnesium Sulfate CRI dose rules from the ExoticRx formulary. Verify against current literature before clinical use; CRI rates differ from bolus dosing and route, dilution, and monitoring matter. Sign in for the complete per-species CRI protocol set.

  • Dog (Domestic)IV
    0.15–0.3 mEq/kgIV CRI over 15-60 min

    Torsades de pointes, hypomagnesemia

    ModeratePlumb's Veterinary Drug Handbook, 9th Ed
  • Cat (Domestic)IV
    0.15–0.3 mEq/kgCRI over 24h

    Hypomagnesemia, refractory seizures

    ModeratePlumb's Veterinary Drug Handbook, 9th Ed

Sample dosing (2 of 2 cited rules)

A dog/cat sample is shown here. Cited dosing for all 2 species — reptiles, birds, pocket pets, livestock, and equine — is free on the per-species pages above. Pro adds the weight-based calculator for every species.

SpeciesRouteDoseFrequencyEvidenceSource
Dog (Domestic)IV0.15–0.3 mEq/kgIV CRI over 15-60 minModeratePlumb's Veterinary Drug Handbook, 9th Ed
Cat (Domestic)IV0.15–0.3 mEq/kgCRI over 24hModeratePlumb's Veterinary Drug Handbook, 9th Ed

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