Side effects:
1-Neuromuscular Manifestations: Neuromuscular symptoms are the most common presenting problem of hypermagnesaemia and magnesium intoxication. Magnesium prevents the release of pre-synaptic acetylcholine from both sympathetic and neuromuscular junctions.(93)Hypermagnesaemia causes blockage of neuromuscular transmission and depresses the conduction system of the heart and the sympathetic ganglia. Clinically, one of the earliest effects of magnesium intoxication is the disappearance of deep tendon reflexes. This is often seen at magnesium concentrations …show more content…
Higher concentration of magnesium may cause severe symptomatic hypotension. (94) Magnesium causes vascular relaxation as well as antagonising the effect of vasopressor agents. (95) This effect is mediated via prostacycline and calcium flux, as cyclo-oxygenase inhibitors and calcium channel blockers prevent the hypotensive effect of magnesium. (96) The negative inotropic effect of hypermagnesaemia may contribute to the hypotension. Other potential factors contributing to the hypotension include central nervous system effects, skeletal muscle paralysis and depression of the carotid baro-receptor. Magnesium is also cardiotoxic. At serum Mg concentrations greater than 3 mmol/L, prolonged PR intervals, increased QRS duration and prolonged QT intervals are seen. Mild bradycardia is observed at concentrations greater than 7 mmol/L, and complete heart block as well as cardiac arrest may occur at concentrations greater than 7 mmol/L. Electrocardiographic changes in hypermagnesaemia are not specific and cannot be relied upon for the diagnosis of magnesium intoxication.
1-Neuromuscular Manifestations: Neuromuscular symptoms are the most common presenting problem of hypermagnesaemia and magnesium intoxication. Magnesium prevents the release of pre-synaptic acetylcholine from both sympathetic and neuromuscular junctions.(93)Hypermagnesaemia causes blockage of neuromuscular transmission and depresses the conduction system of the heart and the sympathetic ganglia. Clinically, one of the earliest effects of magnesium intoxication is the disappearance of deep tendon reflexes. This is often seen at magnesium concentrations …show more content…
Higher concentration of magnesium may cause severe symptomatic hypotension. (94) Magnesium causes vascular relaxation as well as antagonising the effect of vasopressor agents. (95) This effect is mediated via prostacycline and calcium flux, as cyclo-oxygenase inhibitors and calcium channel blockers prevent the hypotensive effect of magnesium. (96) The negative inotropic effect of hypermagnesaemia may contribute to the hypotension. Other potential factors contributing to the hypotension include central nervous system effects, skeletal muscle paralysis and depression of the carotid baro-receptor. Magnesium is also cardiotoxic. At serum Mg concentrations greater than 3 mmol/L, prolonged PR intervals, increased QRS duration and prolonged QT intervals are seen. Mild bradycardia is observed at concentrations greater than 7 mmol/L, and complete heart block as well as cardiac arrest may occur at concentrations greater than 7 mmol/L. Electrocardiographic changes in hypermagnesaemia are not specific and cannot be relied upon for the diagnosis of magnesium intoxication.