Neostigmine Pharmacology

Neostigmine

About Neostigmine
Para-sympathomimetic, a reversible Anticholinesterase, In Myasthenia gravis treatment,an adjunct in general anaesthesia, Curare antagonist.
Mechanism of Action of Neostigmine
It inhibits the destruction of acetylcholine by cholinesterase (by competing with acetylcholine for attachment to acetyl cholinesterase) and thus prolongs and intensifies the physiological actions of acetylcholine. It facilitates transmission of impulses across the myoneural junction by increasing the amount of acetylcholine at the nerve endings. Increased levels of acetyl choline allow the remaining receptors to function more efficiently. It also has direct effects on skeletal muscle fibres. The anticholinesterase actions of Neostigmine are reversible. Neostigmine is used in the treatment of myasthenia gravis and has been used as an alternative to Edrophonium in the diagnosis of myasthenia gravis.
General anaesthesia: This is used to antagonize the action of Nondepolarizing muscle relaxants. Once muscle paralysis is no longer desired, acetyl cholinesterase inhibitors are combined with a muscarinic receptor antagonist such as Glycopyrrolate or Atropine to offset the muscarinic activation resulting from esterase inhibition
Pharmacokinets of Neostigmine
Absorption- Slowly absorbed after oral administration
Distribution- Widely distributed in the body.15-25% bound to the plasma proteins
Metabolism - Undergo slow hydrolysis by acetyl cholinesterase and also by plasma esterases. It is metabolized in liver to its metabolites
Excretion - Unchanged drug (up to 70%) and alcoholic metabolite (30%) are excreted in the urine
Onset of Action for Neostigmine
Orally 45-75 minutes; injection 20 minutes.
Duration of Action for Neostigmine
2-4 hours
Half Life of Neostigmine
15.4 to 30.1 minutes.
Side Effects of Neostigmine
1. Erythmias
2. Hypotension
3. Tachycardia
4. AV block
5. Cardiac arrest
6. Syncope
7. Convulsions
8. Dizziness
9. Headache
10. Dysarthria
11. Dysfonia
12. GI disturbances, increased secretions
13. Skin rash
14. Thrombophlebitis
15. Muscle cramps & spasm
16. Laryngospasm
17. Respiratory depression
18. Urinary frequency and incontinence
Contra-indications of Neostigmine
1. Hypersensitivity to the drug or any other ingredients of it
2. Mechanical urinary obstruction
3. Intestinal obstruction
Special Precautions while taking Neostigmine
1. Epilepsy
2. Bronchial asthma
3. Bradycardia
4. Recent coronary occlusion
5. Hyperthyroidism
6. Cardiac disorders
7. Urinary retention
8. Peptic ulcer
9. Parkinson`s disease
Pregnancy Related Information
Contraindicated
Old Age Related Information
Use with caution
Breast Feeding Related Information
Use with caution
Children Related Information
Use with caution
Indications for Neostigmine
1. Myasthenia gravis
2. Curare antagonist
3. Urinary retention
4. Failure of function of part of the gut causing an obstruction (paralytic ileus)
5. As an adjunct in general anaesthesia
Interactions for Neostigmine
Aminoglycoside antibiotics: Neuromuscular blockade potentiated.
Anticholinesterase drugs: In myasthenic patients receiving anticholinesterase muscle stimulants exercise caution since symptoms of anticholinesterase overdose (cholinergic crisis) may mimic under dosage (myasthenic weakness).
Corticosteroids: Anticholinesterase effect of neostigmine blunted.
Depolarising muscle relaxants: Neostigmine prolongs phase 1 block of these drugs.
Magnesium: May antagonise the effects of neostigmine.
Succinylcholine: Neuromuscular blocking effects enhanced- prolonged respiratory depression with extended periods of apnoea.
Typical Dosage for Neostigmine
General dose -
Oral-
Adults-
15-30mg daily
Intravenous-
1-5mg with atropine 0.4-1.25mg
Children-
I.M. /I.V. /SC-
0.01-0.04mg/kg every 2-3 hours
Oral-
2 mg/kg/day divided every 3-4 hours.
Note: Interval between 2 doses is important and should be individualized.
Schedule of Neostigmine
N/A
Storage Requirements for Neostigmine
Store at room temperature, away from heat and direct light. Keep out of the reach of children.
Effects of Missed Dosage of Neostigmine
Take the missed dose as soon as noticed and if it is the time for next dose then skip the missed dose. Continue the regular schedule. Do not double the dose.
Effects of Overdose of Neostigmine
Give symptomatic and supportive treatment. Muscarinic effects are controlled with IV atropine sulfate (1 to 2 mg) followed by IM atropine sulfate every 2 to 4 hours. Assistance of ventilation may be required if respiration is severely depressed.

Home Delivery for Neostigmine in Your City

Medicine India is just a publishing medium for medicine related information and does not provide services or sales of medicines including neostigmine.

However, we do publish a comprehensive directory of Pharmacies, Chemists and Druggists in cities all over India. You can use this directory to find the medicine stores in your city (or area) that provide home delivery services for neostigmine and other medicines and health products. Home delivery services for neostigmine may be free or they may cost you depending on the pharmacy and the minimum order requirements. It would be best to get this clarified while placing the order.

Please be aware that you should take neostigmine only if a doctor has recommended or prescribed it. Some or all pharmacies who provide a home delivery service for medicines might insist on a prescription for neostigmine before they complete the sale. You can get this information while placing the order for neostigmine with the pharmacy.

Neostigmine is a generic medicine name and there are several brands available for it. Some of the brands for neostigmine might be better known than neostigmine itself. If the pharmacy that's willing to deliver medicines to your home doesn't have neostigmine in stock, you can ask for one of the branded alternatives for neostigmine.