Pyridostigmine
MESTINON
Pronunciation: peer-id-oe-STIG-meen
What it isPeripherally acting acetylcholinesterase inhibitor; symptomatic treatment of myasthenia gravis.
Why this oneIts longer action and oral use make it the standard symptomatic maintenance agent, unlike neostigmine.
What limits itCholinergic crisis can mimic myasthenic crisis; bradycardia, diarrhea, cramping, and secretions signal excess.
FDA-approved for
- myasthenia gravis (~1955)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Myasthenia gravis | Adults | 60 mg, individualized | ~600 mg/day (ten 60 mg tablets), spaced for max relief | ~1500 mg/day (25 tablets) |
Renal Undefined
Hepatic Undefined
Instructions
- Size and frequency individualized to the patient
- Space doses to give maximum relief when maximum strength is needed
Available strengths
- tab 30, 60 mg
- ER tab 180 mg
- sol 60 mg/5 mL
- inj 5 mg/mL
Contraindications
- Mechanical intestinal or urinary obstruction
Cautions
- Use particular caution in bronchial asthma
- Care with atropine used to counteract muscarinic side effects
Adverse reactions
- Muscarinic: nausea, vomiting, diarrhea, abdominal cramps, increased peristalsis/salivation/bronchial secretions, miosis, diaphoresis
- Nicotinic: muscle cramps, fasciculation, weakness
- Skin rash (bromide-related)
Pregnancy Undefined
Lactation Undefined
Cost
Generic entry1990
NO BOXED WARNINGS
Principal riskCholinergic crisis, which mimics myasthenic crisis
Classes and tags
Clinical profile
Legacy pregnancy categoryUnknown / historical label unavailable
Defining liabilityGenerally tolerated at therapeutic doses; clinically important risks are agent-specific and increase with interactions or organ impairment.