Mineral supplement and anticonvulsant
Last reviewed July 2026
Who is this for?
Magnesium sulfate is a mineral medicine that works by replacing low magnesium levels in the body and by calming overactive nerves and muscles, which helps prevent seizures and relax muscles.
Blocks N-methyl-D-aspartate (NMDA) receptors and inhibits acetylcholine release at the neuromuscular junction, reducing neuronal excitability and preventing seizures; also acts as a vasodilator by modulating calcium influx into vascular smooth muscle cells, thereby reducing blood pressure and peripheral resistance.
Seizures during pregnancy (eclampsia), dangerously high blood pressure in pregnancy (pre-eclampsia), low magnesium in the blood, severe asthma attacks, constipation (when taken by mouth), irregular heartbeat
Prescription Required
You need a doctor's prescription to buy this drug.
Explore this drug
Since this drug is usually given by a doctor or nurse in a hospital, missed doses are unlikely. If you are using the oral form for constipation and miss a dose, take it when you remember, but do not double up.
This is a hospital drug, so do not buy magnesium sulfate injection from roadside sellers or patent medicine stores and try to use it at home, as overdose can stop your breathing. Always make sure it is administered by a trained health worker. If you are pregnant and having seizures or severe headaches with high BP, go to the hospital immediately, as magnesium sulfate could save your life.
Magnesium sulfate can be dangerous when combined with calcium channel blockers like nifedipine (commonly used for high blood pressure in Nigeria), so tell your doctor if you use any BP drugs. It can increase the sedating effect of drugs that make you sleepy. Avoid combining with other muscle relaxants without a doctor's guidance.
Check your specific combination
Is it safe to take Magnesium with your other drugs?
Magnesium sulfate is actually commonly used during pregnancy to treat eclampsia and pre-eclampsia, but it must only be given under strict medical supervision in a hospital. Never self-medicate with it during pregnancy or breastfeeding.
Store in a cool, dry place away from direct sunlight and heat. Nigerian weather can be very hot so avoid storing near windows or in cars. Keep the injection sealed until ready for use. Always keep out of reach of children.
For information only: not medical advice. Always talk to a doctor or pharmacist before changing your medication.
Names this drug is sold under, especially in Nigerian and West African pharmacies
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Counterfeit Drug Warning
Fake drugs are a serious problem in Nigeria. Always buy from a registered pharmacy. If the packaging looks different from what is described above, do not use it.