Mestinon SR (Pyridostigmine Bromide)
The prescription medication Metzinon (Pyridostigmine Bromide) is used to treat myasthenia gravis, a muscle disease. It contains Pyridostigmine, an active substance that prevents acetylcholine from being broken down in your body. Nerve gas exposure has led to the use of pyridostigmine by military personnel.
This medication is typically used for extreme muscle fatigue. Its effects can be noticed within a few hours. This medication is typically used only once a day and is long-lasting (similar to the functionality of insulin glargine). However, your doctor or pharmacist may have suggested a different schedule that is more appropriate for you. Take it regularly and continuously to maintain its beneficial effects.
Mestinon (pyridostigmine bromide tablets, USP) inhibits cholinesterase when taken orally. Pyidostigmine bromide is a dimethyl carbamate of 3-hydroxy-1-methyl pyridinium bromide.
Please note, this medication is not insulin and should not be confused with insulin pens, cartridges or vials.
Warnings and Precautions
Do not take this medication if you have an allergy to Pyridostigmine or any ingredients in this Mestinon.
Speak to your doctor about any of your past or existing medical conditions, especially if you have: asthma or COPD, intestinal/stomach blockage, kidney or lung disease, urinary blockage, slow/irregular heartbeat or diabetes.
Notify your doctor of any other medications, supplements, herbal medicines, or vitamins you are currently taking.
Consult your doctor if you are pregnant or breastfeeding.
Do not use this medication if you have bladder or bowel obstruction.
Since this medication can cause blurred vision, do not drive or operate any heavy machinery after taking it. Please do not drink alcohol after taking Mestinon as it can increase specific side effects of Pyridostigmine.
This medication is not approved to be taken by anyone under the age of 18.
In addition to blurred vision and headaches, Mestinon can cause vomiting, rash, abdominal pain, diarrhea, and nausea.
The medication can cause significant side effects such as severe muscle weakness, slurred speech, vision difficulties, and worsening or no improvement in myasthenia gravis. Get in touch with your pharmacist, doctor, or visit a health facility immediately if you experience any serious side effects.
Each individual may react differently to a treatment. Talk to your doctor or pharmacist if you think this medication is causing side effects (including those described here or others). Your physician can help you determine whether or not the medication is the cause of the problem.
Atropine antagonizes the muscarinic effects of pyridostigmine, and this interaction may be utilized to counteract the effects of pyridostigmine. (See Overdose Section)
Pyridostigmine bromide does not antagonize, and in fact, may 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 where indicated, and then a careful adjustment should be made of adjunctive 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 pyridostigmine bromide may have to be increased accordingly.
In severe myasthenia gravis, neostigmine has been combined with pyridostigmine to provide the benefits of short and long-term activity; because of the possibility of reduced intestinal motility and increased toxicity, this combination should be used only under strict medical supervision.
Although the failure of patients to show clinical improvement may reflect under dosage, it can also be indicative of overdosage. As is true of all cholinergic drugs, overdosage of Mestinon (pyridostigmine) may result in cholinergic crisis, a state characterized by increasing muscle weakness which, through the involvement of the muscles of respiration, may lead to death. Myasthenic crisis due to an increase in the severity of the disease is also accompanied by extreme muscle weakness and thus may be difficult to distinguish from the cholinergic crisis on a symptomatic basis. Such differentiation is significant since increases in doses of Mestinon (pyridostigmine) or other drugs of this class in the presence of cholinergic crisis or a refractory or “insensitive” state could have grave consequences.
Mestinen (pyridostigmine) is contraindicated in patients with mechanical intestinal obstruction or urinary obstruction, and patients with bronchial asthma should be cautious when taking it. As discussed below, atropine should be used with caution to counteract side effects.
Pregnant or lactating women have not been proven safe when taking Mestinon (pyridostigmine). The potential benefits and risks of using Mestinon (pyridostigmine) during pregnancy must be weighed against the potential hazards to the mother and child.
As with most medications, this product should be stored at room temperature. Store it in a secure location where it will not be exposed to excessive heat, moisture, or direct sunlight. Make sure that any leftover portion is disposed of safely.
Keep all your medications out of the reach of children and pets and return any unused or expired medications to the pharmacy for proper disposal.