Anticholinesterases

They bind reversibly to acetylcholinesterase and block it, so acetylcholine is broken down more slowly and builds up at synapses. At the neuromuscular junction the extra acetylcholine strengthens weak muscles in myasthenia gravis and outcompetes non-depolarizing blockers. It also boosts muscarinic effects on the gut, glands, airways and heart, which cause most side effects.

• NeostigmineShorter acting than pyridostigmine and given by injection, mainly to reverse non-depolarizing blockade at the end of surgery.
• PyridostigmineLonger acting than neostigmine with fewer gut effects, and taken by mouth, so it suits long-term treatment of myasthenia gravis.

• Myasthenia gravis
• Reversing non-depolarizing muscle relaxants after surgery
• Urinary retention after surgery

• Slow heart rateKnown forSerious
• Cholinergic crisis: weakness from too much drugKnown forSerious
• Diarrhea and abdominal cramps
• Passing urine often, or incontinence
• Small pupils (miosis)
• Bronchospasm and extra bronchial secretionsSerious
• Nausea and vomiting
• Watery eyes
• Excess saliva
• Sweating

What the class has in common. Each drug's card has its own, and Known for marks what an exam expects you to know.

• Contraindicated in mechanical obstruction of the gut or urinary tract.
• Asthma: they can trigger bronchospasm.
• Slow heart rate or arrhythmia: risk of marked slowing; atropine or glycopyrrolate is given with them when reversing blockade.
• They prolong, rather than reverse, a depolarizing block such as suxamethonium's.

Written for biofideX in plain words, after checking these references:

• Neostigmine methylsulfate injection: label (DailyMed)
• Pyridostigmine bromide tablets: label (DailyMed)
• Neostigmine methylsulfate injection: SmPC (emc)
• Acetylcholinesterase inhibitor (NCI Thesaurus)

For learning pharmacology, not for treatment decisions: no doses are given, and a prescriber, pharmacist or the product's own label is the word on any one patient. Spotted a mistake? Tell us and we'll correct it.