Magnesium, IVDose, contraindications and adverse effects for Cats, Cattle, Dogs, Goats, Horses, Pigs and Sheep.

Injectable magnesium salt used parenterally to correct hypomagnesemia or as an antiarrhythmic/anticonvulsant adjunct. Magnesium is used parenterally in many species for treatment of hypomagnesemia and to resolve clinical signs associated with hypomagnesemia (eg, seizures, refractory arrhythmias). It is also used in swine for adjunctive therapy of malignant hyperthermia. A case report of administering magnesium IV to a dog with generalized tetanus has been published. In dogs and cats, routine use of magnesi

Magnesium is used as a cofactor in a variety of enzyme systems and is involved in muscular excitement and neurochemical transmission.

Parenteral magnesium is contraindicated in patients with myocardial damage or atrioventricular block. Because magnesium is renally cleared, it should be used with caution in patients with impaired renal function, as hypermagnesemia and magnesium intoxication can result. Consider reducing the dose for patients with renal insufficiency. When administering magnesium IV for treatment of hypomagnesemia, consider reducing potassium supplementation as hyperkalemia may result.

Adverse effects of parenteral magnesium are generally the result of magnesium overdose and may include nausea, vomiting, drowsiness or other CNS depressant effects, muscular weakness, bradycardia, hypotension, hypocalcemia, respiratory depression, and prolonged QT intervals on ECG. Very high magnesium levels may cause neuromuscular blocking activity and eventually cardiac arrest.

■ Serum magnesium: Total serum magnesium (tMg) measures magnesium in the serum in its 3 forms (ie, ionized, bound, and complexed). Unfortunately, it does not correlate well with total body magnesium but may be useful, especially when suspect-ing hypermagnesemia.