Generic
Pyridostigmine
2 brands available in the market
At a glance
Pyridostigmine is a cholinesterase inhibitor used for myasthenia gravis, paralytic ileus, and postoperative urinary retention. It facilitates impulse transmission across the myoneural junction by inhibiting the destruction of acetylcholine.
Description
Pyridostigmine is an orally active cholinesterase inhibitor that inhibits acetylcholine destruction, allowing freer transmission of nerve impulses across the neuromuscular junction. It is an analog of neostigmine but has a longer duration of action and fewer gastrointestinal side effects.
Indications
- Myasthenia gravis
- Paralytic ileus
- Postoperative urinary retention
Therapeutic class
Drugs used in Myasthenia Gravis
Pharmacological class
Cholinesterase Inhibitor
Pharmacology
Pyridostigmine inhibits acetylcholine destruction, facilitating nerve impulse transmission across the neuromuscular junction. It has a longer duration of action and fewer GI side effects compared to neostigmine. It also has a direct cholinomimetic effect on skeletal muscles.
Mechanism of action
Improves muscle function by inhibiting acetylcholine destruction.
Dosage
Adult Dose (Oral):
- Myasthenia gravis: 30-120 mg in divided doses; up to 0.3-1.2 g daily
- Paralytic ileus/Postoperative urinary retention: 60-240 mg daily
Pediatric Dose (Oral):
- Myasthenia gravis (<6 years): 30 mg initially; (6-12 years): 60 mg initially; total daily 30-360 mg (15-30 mg increments)
- Paralytic ileus/Postoperative urinary retention: 15-60 mg daily
- Neonates: 5-10 mg every 4 hours (30-60 min before feeding)
Administration
- Take on an empty stomach (preferably)
- Swallow tablet whole; do not chew, crush, or break
Missed dose
If you miss a dose, take it as soon as you remember; skip if it's almost time for next dose; do not double the dose.
Side effects
Side Effects:
- Nausea
- Excessive salivation
- Diarrhea
- Blurred vision
- Shortness of breath
- Watery eyes
- Abdominal pain
- Altered urinary frequency
- Sweating
- Headache
- Dizziness
- Muscle fasciculation
- Muscle cramps
Precautions & warnings
- May affect driving ability; do not drive if dizzy or blurred vision occurs
- Overdose can cause extreme muscle weakness
- Avoid alcohol (may worsen side effects)
- Caution in renal disease, Parkinson's, asthma, stomach disorders
Contraindications
- Mechanical GI or urinary obstruction
Drug interactions
- Anti-glaucoma drugs: May exacerbate night vision problems
- Non-depolarizing muscle relaxants (pancuronium, vecuronium): Antagonizes effect
- Depolarizing muscle relaxants (suxamethonium): Prolongs effect
Food interactions
It is not known whether it is safe to consume alcohol with Pyridostigmine.
Use in pregnancy
Use in Pregnancy: Generally considered safe; animal studies have shown low or no adverse effects; limited human studies.
Pregnancy Category: C — always consult a doctor before taking during pregnancy.
Use in lactation
Use in Lactation: Probably safe; limited human data suggests no significant risk.
Pediatric use
Pediatric dose based on age; neonates usually do not require treatment beyond 8 weeks.
Geriatric use
Caution required in elderly patients; dose adjustment may be needed.
Renal / hepatic impairment
Renal Impairment: Caution in kidney disease; lower initial dose may be needed; consult your doctor.
Hepatic Impairment: Limited information on use in liver disease; consult your doctor.
Overdose effects
Overdose: Muscarinic and nicotinic effects (nausea, diarrhea, abdominal cramps, muscle weakness); treatment: atropine (for muscarinic effects), symptomatic supportive care.
Storage conditions
Store in a cool and dry place, protected from light; keep out of reach of children.
Chemical structure
Pyridostigmine