Pharmacology Mnemonics - Flash Cards

Name: Tacrine (Cognex)

Class: Anticholinesterase Agent: Acridinamine

Mech.: Blocks AChE and BuChE. Inhib. M1 and M2 receptors. Weak nicotinic blocker. ­ release of ACh from nerve endings.

Absorption:

Dist.: Good CNS.

Metab.:

Excretion, t½:

Toxicity/S.E.s: Reversible liver damage. Avoid in cases of asthma, coronary insufficiency, peptic ulcers.

Utility: Alzheimer’s disease

Special Features:

Name: Echothiophate (Phospholine)

Class: Anticholinesterase Agent: Organophosphate

Mech.: Binds irreversibly to AChE

Absorption: Eye drops.

Dist.:

Metab.:

Excretion, t½: Long-lasting inhibition—days to weeks.

Toxicity/S.E.s: Toxic doses first stim. then depress autonomic ganglia, neuromusc. jxns, and central sites. Treat w/heroic doses of atropine for muscarinic effects, pralidoxine for neuromusc effects.

Utility: Topical eye applic. to treat glaucoma. For closed-angle glaucoma, stim. constriction of iris sphincter ® iris removed from entrance to trabecular space. For open-angle glaucoma, stim. sphincter and ciliary body contraction ® ­ patency of trabecular network. Topical to treat crossed eyes.

Special Features: Bond btwn drug and AChE must age before becoming irreversible. While bond is aging, drugs such as pralidoxime can reactivate AChE.

Name: Isoflurophate (Floropryl, DFP)

Class: Anticholinesterase Agent: Organophosphate

Mech.: Binds irreversibly to AChE

Absorption:

Dist.: Acts mostly at autonomic sites. Some neuromusc. action.

Metab.:

Excretion, t½: Long-lasting inhibition—days to weeks.

Toxicity/S.E.s: Toxic doses first stim. then depress autonomic ganglia, neuromusc. jxns, and central sites. Treat w/heroic doses of atropine for muscarinic effects, pralidoxime for neuromusc effects.

Utility:

Special Features: Bond btwn drug and AChE must age before becoming irreversible. While bond is aging, drugs such as pralidoxime can reactivate AChE.

Name: Pyridostigmine (Mestinon)

Class: Anticholinesterase Agent: Carbamate (Quaternary Amine)

Mech.: Substrate for AChE. Competitive inhib. of interaction btwn ACh and AChE. Stim. postjxnl nicotinic (i.e., muscular) receptors.

Absorption: Oral adequate.

Metab.: Slowly hydrolyzed by AChE

Dist.: No CNS. Acts mostly at neuromusc sites. Some autonomic action.

Excretion, t½: Slowly hydrolyzed by AChE

Toxicity/S.E.s: Toxic doses first stim. then depress autonom. ganglia, NM jxns, and central sites. Dose too large ® skel. muscle weakness = cholinergic crisis. Too small ® muscle weakness = myasthenic weakness. Avoid in cases of asthma, coronary insufficiency, peptic ulcers.

Utility: Treat myasthenia gravis. Longer acting than neostigmine; used more freq.

Special Features: Non-selective. Stim. cholinergic receptors throughout CNS and PNS. Inhib. AChE and BuChE.

Name: Neostigmine (Prostigmine)

Class: Anticholinesterase Agent: Carbamate (Quaternary Amine)

Mech.: Substrate for AChE. Competitive inhib. of interaction btwn ACh and AChE. Stim. postjxnl nicotinic (i.e., muscular) receptors.

Absorption: Oral adequate.

Dist.: No CNS. Acts mostly at neuromusc sites. Some autonomic action.

Metab.: Slowly hydrolyzed by AChE

Excretion, t½: Slowly hydrolyzed by AChE

Toxicity/S.E.s: Toxic doses first stim. then depress autonomic ganglia, neuromusc. jxns, and central sites. Dose too large ® skeletal muscle weakness = cholinergic crisis. Dose too small ® skeletal muscle weakness = myasthenic weakness. Avoid in cases of asthma, coronary insufficiency, peptic ulcers.

Utility: Treat myasthenia gravis. Treat post-op paralytic ileus and urinary bladder atony. Antag. NM blockade of curare-like agents.

Special Features: IV ® Non-selective. Stim. cholinergic receptors throughout CNS and PNS. Inhib. AChE and BuChE. Musc. effects prevented by pretreatment w/atropine.

Name: Physostigmine (Antilirium)

Class: Anticholinesterase Agent: Carbamate (Tertiary Amine)

Mech.: Substrate for AChE. Competitive inhib. of interaction btwn ACh and AChE.

Absorption:

Dist.: Enters CNS. Acts mostly at autonomic sites. Some neuromusc. action.

Metab.: Slowly hydrolyzed by AChE

Excretion, t½: A few hours.

Toxicity/S.E.s: Toxic doses first stim. then depress autonomic ganglia, neuromusc. jxns, and central sites. Avoid in cases of asthma, coronary insufficiency, peptic ulcers.

Utility: DOC to antag. toxic effects of atropine-like (anticholinergic) drugs.

Special Features: Non-selective. Stim. cholinergic receptors throughout CNS and PNS. Inhib. AChE and BuChE.

Name: Edrophonium (Tensilon)

Class: Anticholinesterase Agent: Choline Analog

Mech.: Combines w/AChE. Competitively prevents interaction of ACh w/AChE.

Absorption:

Dist.: No CNS. Acts mostly at neuromusc sites. Some autonomic action.

Metab.:

Excretion, t½: Brief duration of action (several min.) because binding is rapidly reversible.

Toxicity/S.E.s: Toxic doses first stim. then depress autonomic ganglia, neuromusc. jxns, and central sites. IV—­ skeletal muscle strength = myasthenic weakness; ¯ strength = cholinergic crisis. Avoid in cases of asthma, coronary insufficiency, peptic ulcers.

Utility: IV—test for myasthenia gravis. Antag. NM blockade of curare-like agents. Treat paroxysmal supraventricular tachycardia.

Special Features: IV ® Non-selective. Stim. cholinergic receptors throughout CNS and PNS. Inhib. AChE and BuChE.