PROSTIG

Neostigmine Methyl Sulphate is used for - • Reversal of non-depolarizing neuromuscular blockade for surgical anesthetic rocedures • The prevention & treatment of postoperative distention & urinary retention after mechanical obstruction has been excluded • Treatment of the systemic control of Myasthenia gravis when oral therapy is impractical

Cholinesterase Inhibitor; Parasympathomimetic

Neostigmine Methylsulfate Injection, an anticholinesterase agent is a sterile, nonpyrogenic solution of Neostigmine Methylsulfate in Water for Injections intended for intramuscular (IM), intravenous (IV) or subcutaneous (SC) administration. Neostigmine is a parasympathomimetic, specifically, a reversible cholinesterase inhibitor. The drug inhibits acetylcholinesterase which is responsible for the degredation of acetylcholine. So, with acetylcholinesterase inhibited, more acetylcholine is present By interfering with the breakdown of acetylcholine, neostigmine indirectly stimulates both nicotinic and muscarinic receptors which are involved in muscle contraction.. It does not cross the blood-brain barrier.

Adults: By intramuscular or subcutaneous injection: Symptomatic control of myasthenia gravis: 1 ml of the 1:2000 solution (0.5 mg) intramuscularly or subcutaneously. Subsequent dose should be based on the individual patient’s response. Treatment of post-operative distention: 1 ml of the 1:2000 solution (0.5 mg) intramuscularly or subcutaneously or as required. Prevention of post-operative distention & urinary retention: 1 ml of the 1:4000 solution (0.25 mg) intramuscularly or subcutaneously as soon as possible after operation; repeat every 4-6 hours for 2-3 days. Treatment of urinary retention: 1 ml of the 1:2000 solution (0.5 mg) intra-muscularly or subcutaneously. If urination does not occur within an hour, the patient should be catheterized. After the patient has voided, or the bladder has been emptied, continue the 0.5 mg injection every 3 hrs, for at least 5 injections. Reversal of Effects of Non- epolarizing Neuromuscular Blocking Agents; when Neostigmine is administered intravenously, it is recommended that Atropine Sulphate (0.6-1.2 mg) also be given intravenously using separate syringe. The usual dose is 0.5 to 2 mg is given by slow intravenous injection, repeated as required. On exceptional cases total dose should be exceed 5 mg. Neonates: 50-250 micrograms every 4 hrs. Children: 200-500 micrograms as recommended.

Neostigmine Methylsulfate injection does not antagonize, and may in fact prolong, the Phase I block of depolarizing muscle relaxants such as succinylcholine or decamethonium. Certain antibiotics, especially neomycin, streptomycin and kanamycin, have a mild but definite nondepolarizing blocking action which may accentuate neuromuscular block. These antibiotics should be used in the myasthenic patient only when definitely indicated, and then careful adjustment should be made of the anticholinesterase dosage. Local and some general anesthetics, antiarrhythmic agents and other drugs that interfere with neuromuscular transmission should be used cautiously, if at all, in patients with myasthenia gravis; the dose of Neostigmine Methylsulfate may have to be increased accordingly.

Neostigmine is contraindicated in patients with known hypersensitivity to the drug. It is also contraindicated in patients with peritonitis or mechanical obstruction of the intestinal or urinary tract. Asthma, bradycardia, recent myocardial infarction, epilepsy, hypotension, parkinsonism, vagotonia, peptic ulceration. Atropine or other antidote to muscarinic effccts may be necessary (particularly when Neostigmine is given by injection), but it should not be given routinely as it may mask signs of overdose.

Nausea, vomiting, increased salivation, diarrhea & abdominal cramps (more marked with high doses). Signs of verdose are increased gastrointestinal discomfort, bronchial secretions & sweating, involuntary defecation & micturition, miosis, nystagmus, bradycardia, hypotension, agitation, excessive dreaming & weakness eventually leading to fasciculation & paralysis.

Pregnancy category C. But use during lactation hasn’t been determined.

Overdosage with Neostigmine Methylsulfate can cause cholinergic crisis, which is characterised by increasing muscle weakness. Myasthenic crisis is due to an increase in severity of the disease and may be difficult to distinguish from cholinergic crisis on a symptomatic basis. Cholinergic crisis can lead to respiratory paralysis, which may result in death, while myasthenic crisis is extreme muscle weakness. The differentiation between the two crises is extremely important as treatment is different for each. The two types of crises can be differentiated by the use of edrophonium and clinical judgement.

Store at controlled room temperature protected from light. Any portion of the contents remaining should be discarded.

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