Pharm Drug Action Exam #1 Drugs

Direct-acting Cholinomimetic Agents

Acetylcholine, Carbachol, Pilocarpine, Cevimeline, Bethanechol, Nicotine, Varenicline

Nicotine Brands

Nicoderm (topical), Nicotrol (inhaled/nasal), Nicorette (topical or gum/lozenge), Commit

Varenicline Brand

Chantix

Indirect-acting Cholinomimetic Agents

Edrophonium, Echothiophate, Galantamine, Donepezil, Rivastigmine, Neostigmine, Pyridostigmine, Physostigmine

Galantamine Brand

Razadyne

Donepezil Brand

Aricept

Rivastigmine Brand

Exelon

Anticholinergic (Parasympatholytic) Agents

Atropine, Dicyclomine, Glycopyrrolate, Hyoscyamine, Methscopalomine, Propantheline, Scopolamine, Belladona alkaloids

Dicyclomine Brand

Bentyl

Hyoscyamine Brands

Anaspaz, Levsin

Scopolamine Brand

Transderm-scop

Belladona Alkaloids Brands

Donnatal, Librax

Genitourinary Smooth Muscle Relaxant Agents

Darifenacin, Fesoterodine, Flavoxate, Oxybutynin, Solifenacin, Tolterodine, Trospium

Darifenacin Brand

Enablex

Fesoterodine Brand

Toviaz

Oxybutynin Brands

Ditropan XL, Oxytrol

Solifenacin Brand

Vesicare

Tolterodine Brands

Detrol, Detrol XL

Selective Alpha-1 Adrenergic Agonists

Midodrine, Phenylephrine

Non-Selective Beta Adrenergic Agonist

Isoproterenol

Selective Beta-1 Adrenergic Agonist

Dobutamine

Selective Beta-3 Adrenergic Agonist

Mirabegron

Non-Selective Alpha and Beta Adrenergic Agonists

Dopamine, Epinephrine, Norepinephrine, Ephedine, Pseudoephedrine, Droxidopa

Norepinephrine Brand

Levophed

Pseudoephedrine Brand

Sudafed

Non-Selective Alpha Blockers

Phenoxybenzamine, Phentolamine

Selective Alpha-1 Blockers

Prazosin, Terazosin, Doxazosin

Prazosin Brand

Minipress

Doxazosin Brands

Cardura, Cardura XL

Selective Alpha-1A Blockers

Alfuzosin, Silodosin, Tamsulosin

Silodosin Brand

Rapaflo

Tamsulosin Brand

Flomax

Tyrosine Hydroxylase Inhibitor

Metyrosine

Terazosin Brand

Hytrin

Beta-1 Selective Antagonists

Acebutolol, Atenolol, Betazolol, Bisoprolol, Esmolol, Metoprolol tartrate, Metoprolol succinate

Atenolol Brand

Tenormin

Bisoprolol Brand

Zebeta

Metoprolol Tartrate Brand

Lopressor

Metoprolol Succinate Brand

Toprol XL

Beta-1 Selective Antagonist / Nitric Oxide Dependent Vasodilator

Nebivolol

Nebivolol Brand

Bystolic

Non-Selective Beta-1/Beta-2 Antagonists

Nadolol, Penbutolol, Pindolol, Propranolol, Sotalol, Timolol

Nadolol Brand

Corgard

Propranolol Brand

Inderal

Sotalol Brands

Betapace, Betapace AF

Non-Selective Alpha/Beta Antagonists

Carvedilol, Labetalol

Carvedilol Brands

Coreg, Coreg CR

Ophthalmic Beta Antagonists

Betaxolol, Carteolol, Timolol, Levobunolol

Centrally-Acting Alpha-2 Adrenergic Agonists

Clonidine, Guanfacine, Methyldopa, Guanabenz

Clonidine Brands

Catapres, Catapres-TTS

Guanfacine Brands

Intuniv, Tenex

Adrenergic Neuronal Blocking Agent

Reserpine

Ganglionic Blocking Agent

Mecamylamine

Direct-Acting Cholinomimetic Systemic Cholinergic Side Effects

Bradycardia, hypotension, breathing difficulties, flushing and sweating, epigastric distress, abdominal cramps, diarrhea, urinary urgency

Acetylcholine/Carbachol Indications

Anterior segment eye surgery when rapid miosis is required

Acetylcholine/Carbachol Side Effects

Common: corneal edema and clouding

Serious: retinal detachment

Minimal risk of systemic effects due to short DOA

Pilocarpine Ophthalmic Indications

Glaucoma to lower IOP, miosis induction

Pilocarpine/Cevimeline PO Indication

Dry mouth (especially in patients with Sjogen’s syndrome)

Pilocarpine/Cevimeline Side Effects

Common: Decreased accommodation to low light (nyctalopia- “night blindness”) (ophth), Sweating and GI overactivity (PO)

Cholinergic side effects related to the extension of the MOA is seen with PO formulation

Direct-Acting Cholinomimetic MOA

Bind to and activate muscarinic or nicotinic receptors. (Agents vary in their relative selectivity to receptors or receptor subtypes.)

Bethanechol Indication

Urinary retention (not due to obstruction)

Bethanechol Main Side Effect

Urinary urgency

Nicotine/Varenicline Indication

Smoking cessation

Nicotine Considerations

Agonist at N_N and N_M receptors. Crosses the BBB.

Nicotine Precautions/Side Effects

Dependence, withdrawal

Varenicline MOA

Partial neuronal alpha-4-beta-2 nicotinic receptor agonist that prevents nicotine stimulation

Varenicline Boxed Warning

Serious neuropsychiatric events

Varenicline Side Effects

Nausea, bizarre dreams, insomnia

Varenicline Considerations

Renal elimination- dose adjustment necessary in renal impairment. Titrate dose upon initiation to decrease GI side effects. REMS (Risk Evaluation and Mitigation Strategy) medication guide required.

Indirect-Acting Cholinomimetic MOA

Inhibits acetylcholinesterase and prevents the hydrolysis of acetylcholine to choline and acetic acid resulting in increased concentrations of endogenous acetylcholine at the synaptic clefts and neuroeffector junctions.

Edrophonium Indication

Diagnosis and assessment of myasthenia gravis

Edrophonium Considerations

Onset: Rapid (30-60 seconds) DOA: Short (~10 minutes)

Edrophonium Precautions

May cause cholinergic crisis- have atropine available.

Edrophonium Side Effects

Common: GI, increased salivation, sweating, urinary urgency

Serious: bradycardia, arrhythmias

Echothiophate Considerations

Organophosphate- more lipophilic compounds used for insecticides or poisons (malathion/parathion). Very long DOA due to irreversible covalent bonding and aging.

Galantamine/Donepezil/Rivastigmine Indications

Mild to moderate alzheimer type dementia

Galantamine Considerations

Avoid use in severe renal and hepatic impairment

Donepezil Considerations

CYP2D6 and 3A4 metabolism

Rivastigmine Considerations

Cholinesterase-mediated hydrolysis but reduce dose in hepatic dysfunction. Causes less GI symptoms. Food decreases PO absorption. Counsel patients to remove old patch.

Galantamine/Donepezil/Rivastigmine Side Effects

Nausea, vomiting, diarrhea, anorexia, fatigue, weight loss

Neostigmine Indication

Reversal of non-depolarizing neuromuscular blockers

Pyridostigmine Indication

Myasthenia gravis

Neostigmine MOA

Covalently bonds to enzyme leading to longer DOA

Pyridostigmine Considerations

Primarily renal excretion- reduce dose in renal impairment.

Physostigmine Considerations

Tertiary amine- good CNS penetration

Neostigmine/Pyridostigmine/Physostigmine Side Effects

Common: GI effects, increased salivation

Serious: bradycardia

Anticholinergics (Parasympatholytics) MOA

Competitive muscarinic receptor antagonists. (Agents differ slightly in selectivity and side effects.)

Atropine Indications

ACLS (Advanced Cardiovascular Life Support) protocol, Bradycardia, Antidote (for muscarinic mushroom or organophosphate poisoning)

Atropine/Dicyclomine/Hyoscyamine Considerations

Tertiary amine- Both CNS and peripheral effects

Atropine Side Effects

Common: Sedation, anticholinergic effects

Serious: CNS disturbances

Atropine Precaution

Light sensitivity

Dicyclomine Indication

IBS

Dicyclomine/Glycopyrrolate/Hyoscyamine Contraindications

Obstructive uropathy, GI obstruction

Dicyclomine/Glycopyrrolate/Hyoscyamine Precautions

Heat prostration due to decreased sweating

Glycopyrrolate Considerations

Fewer CNS side effects

Hyoscyamine Indications

IBS, infant colic, anticholinesterase antidote

Scopolamine Indication

Antiemetic sedative

Genitourinary Smooth Muscle Relaxant MOA

Competitive muscarinic receptor antagonist. (Agents differ slightly in selectivity and side effects.)

Darifenacin/Fesoterodine/Solifenacin/Tolterodine/Trospium Indication

Overactive bladder

Flavoxate Indications

Symptomatic relief for cystitis, urethritis, prostatitis