Drug: Hemicholinium
(Cholinergic)
Class: Inhibitor of ACh synthesis (blocks choline uptake)
Clinical Applications: Research tool; not used therapeutically
Common Side Effects: Not clinically used
Serious Adverse Effects: Experimental toxicity
Contraindications: Not applicable (not for clinical use)
Therapeutic Considerations: Blocks high-affinity choline transporter → ↓ ACh synthesis; important in experimental neuropharmacology
Drug: Vesamicol
(Cholinergic)
Class: Inhibitor of ACh storage
Clinical Applications: Experimental use only
Common Side Effects: Not used in humans Serious Adverse Effects: Not applicable
Contraindications: N/A
Therapeutic Considerations: Inhibits vesicular ACh transporter (VAChT), preventing ACh from entering synaptic vesicles
Drug: Botulinum Toxin
(Cholinergic)
Class: Neurotoxin; inhibits ACh release
Clinical Applications: Dystonia, cosmetic reduction of wrinkles, chronic migraine, hyperhidrosis, strabismus
Common Side Effects: Local muscle weakness, ptosis, flu-like symptoms
Serious Adverse Effects: Dysphagia, respiratory depression if systemically absorbed
Contraindications: Infection at injection site, hypersensitivity
Therapeutic Considerations: Cleaves SNARE proteins needed for vesicle fusion, preventing ACh release; effects are long-lasting but reversible
Drug: Scopolamine
(Cholinergic)
Class: Muscarinic receptor antagonist
Clinical Applications: Motion sickness (transdermal), postoperative nausea
Common Side Effects: Dry mouth, drowsiness, blurred vision
Serious Adverse Effects: Hallucinations, confusion (especially in elderly)
Contraindications: Narrow-angle glaucoma
Therapeutic Considerations: Crosses the blood-brain barrier; central effects dominate at therapeutic doses
Drug: Atropine
(Cholinergic)
Class: Muscarinic receptor antagonist
Clinical Applications: Bradycardia, organophosphate poisoning, pre-op secretion reduction, pupil dilation for eye exams
Common Side Effects: Dry mouth, tachycardia, photophobia
Serious Adverse Effects: Hyperthermia, delirium, urinary retention
Contraindications: Glaucoma, urinary tract obstruction
Therapeutic Considerations: Non-selective M antagonist; dose-dependent tissue effects (low = salivary/gastric, high = heart and eyes)
Drug: Ipratropium
(Cholinergic)
Class: Muscarinic antagonist (inhaled)
Clinical Applications: COPD, asthma (less effective for acute bronchospasm than β2 agonists)
Common Side Effects: Dry mouth, cough
Serious Adverse Effects: Rare systemic effects due to poor absorption
Contraindications: Hypersensitivity to atropine derivatives or soy/peanut (formulation dependent)
Therapeutic Considerations: Quaternary amine → minimal CNS effects; short-acting bronchodilator
Drug: Tiotropium
(Cholinergic)
Class: Long-acting muscarinic antagonist (LAMA)
Clinical Applications: Maintenance therapy for COPD, sometimes used in asthma
Common Side Effects: Dry mouth, constipation, urinary retention
Serious Adverse Effects: Paradoxical bronchospasm, atrial fibrillation (rare)
Contraindications: Hypersensitivity to tiotropium or lactose (inhaler formulation)
Therapeutic Considerations: Longer duration than ipratropium; once-daily dosing improves adherence
Drug: Solifenacin
(Cholinergic)
Class: Muscarinic M3 receptor antagonist
Clinical Applications: Overactive bladder, urinary urgency/incontinence
Common Side Effects: Dry mouth, constipation, blurred vision
Serious Adverse Effects: Urinary retention, QT prolongation (rare)
Contraindications: Urinary retention, gastric retention, uncontrolled narrow-angle glaucoma
Therapeutic Considerations: Higher selectivity for M3 → fewer CNS effects vs. older antimuscarinics
Drug: Tolterodine
(Cholinergic)
Class: Muscarinic antagonist (M3 receptor antagonist)
Clinical Applications: Overactive bladder symptoms
Common Side Effects: Dry mouth, constipation, headache
Serious Adverse Effects: QT prolongation, confusion (especially in elderly)
Contraindications: Urinary/gastric retention, narrow-angle glaucoma
Therapeutic Considerations: Less M3 selectivity than solifenacin; caution in elderly patients
Drug: Bethanechol
(Cholinergic)
Class: Muscarinic receptor agonist
Clinical Applications: Urinary retention, postoperative ileus
Common Side Effects: Diarrhea, salivation, abdominal cramps
Serious Adverse Effects: Bronchospasm, hypotension, bradycardia
Contraindications: Asthma, GI obstruction, peptic ulcer, bradycardia
Therapeutic Considerations: Selective for muscarinic receptors; does not cross BBB
Drug: Nicotine
(Cholinergic)
Class: Nicotinic receptor agonist
Clinical Applications: Smoking cessation (patches, gums), experimental studies on ganglionic stimulation
Common Side Effects: Nausea, dizziness, headache
Serious Adverse Effects: Arrhythmias, seizures at high doses
Contraindications: Hypersensitivity, caution in cardiovascular disease
Therapeutic Considerations: Stimulates both sympathetic and parasympathetic ganglia; high doses cause receptor desensitization
Drug: Edrophonium
(Cholinergic)
Class: Short-acting acetylcholinesterase inhibitor
Clinical Applications: Diagnosis of myasthenia gravis (Tensilon test)
Common Side Effects: Increased salivation, GI cramping
Serious Adverse Effects: Bradycardia, bronchospasm
Contraindications: Intestinal or urinary obstruction
Therapeutic Considerations: Rapid onset and short duration; does not cross Blood Brain Barrier
Drug: Neostigmine
(Cholinergic)
Class: Reversible acetylcholinesterase inhibitor
Clinical Applications: Myasthenia gravis, reversal of neuromuscular blockade, urinary retention
Common Side Effects: Nausea, diarrhea, bradycardia
Serious Adverse Effects: Cholinergic crisis, bronchospasm
Contraindications: Peritonitis, mechanical obstruction
Therapeutic Considerations: Quaternary compound (does not cross BBB); longer duration than edrophonium
Drug: Physostigmine
(Cholinergic)
Class: Reversible acetylcholinesterase inhibitor
Clinical Applications: Antidote for anticholinergic toxicity (e.g., atropine overdose)
Common Side Effects: Sweating, nausea, bradycardia
Serious Adverse Effects: Seizures, cholinergic crisis
Contraindications: Asthma, cardiovascular disease
Therapeutic Considerations: Tertiary amine; crosses BBB, unlike neostigmine
Drug: Donepezil
(Cholinergic)
Class: Centrally acting acetylcholinesterase inhibitor
Clinical Applications: Alzheimer’s disease (mild to moderate)
Common Side Effects: Nausea, diarrhea, insomnia
Serious Adverse Effects: Bradycardia, syncope
Contraindications: Hypersensitivity
Therapeutic Considerations: Long half-life allows once-daily dosing; selectively enhances central cholinergic transmission
Drug: Methacholine
(Cholinergic)
Class: Muscarinic receptor agonist
Clinical Applications: Diagnosis of bronchial hyperreactivity (asthma test)
Common Side Effects: Coughing, chest tightness
Serious Adverse Effects: Bronchospasm, hypotension
Contraindications: Severe asthma, cardiovascular disease
Therapeutic Considerations: Inhaled; used under medical supervision only; highly sensitive test for asthma diagnosis
Drug: Succinylcholine
(Cholinergic)
Class: Depolarizing neuromuscular blocker
Clinical Applications: Muscle relaxation during intubation and surgery
Common Side Effects: Muscle fasciculations, postoperative myalgia
Serious Adverse Effects: Malignant hyperthermia, hyperkalemia, apnea
Contraindications: History of malignant hyperthermia, burns, neuromuscular disease
Therapeutic Considerations: Rapid onset, short duration; metabolized by plasma cholinesterases
Drug: Pancuronium
(Cholinergic)
Class: Non-depolarizing neuromuscular blocker
Clinical Applications: Adjunct to anesthesia for muscle paralysis
Common Side Effects: Tachycardia, hypotension
Serious Adverse Effects: Prolonged paralysis, anaphylaxis
Contraindications: Hypersensitivity, caution in renal/hepatic impairment
Therapeutic Considerations: Long-acting agent; reversed by cholinesterase inhibitors (e.g., neostigmine)
Drug: Tubocurarine
(Cholinergic)
Class: Non-depolarizing neuromuscular blocker
Clinical Applications: Historical use in anesthesia for muscle relaxation
Common Side Effects: Hypotension (histamine release), prolonged weakness
Serious Adverse Effects: Respiratory paralysis
Contraindications: Asthma, hypotension, myasthenia gravis
Therapeutic Considerations: Rarely used today; replaced by safer non-depolarizing agents
Drug: Methyltyrosine
(Adrenergic)
Class: Tyrosine hydroxylase inhibitor
Clinical Applications: Treatment of pheochromocytoma (rare adrenal tumor)
Common Side Effects: Sedation, diarrhea, anxiety
Serious Adverse Effects: Extrapyramidal symptoms, hypotension
Contraindications: Hypersensitivity, Parkinson’s disease
Therapeutic Considerations: Depletes catecholamine synthesis; used adjunctively before surgery in pheochromocytoma
Drug: Reserpine
(Adrenergic)
Class: VMAT (vesicular monoamine transporter) inhibitor
Clinical Applications: Rarely used now; previously used for hypertension
Common Side Effects: Nasal congestion, GI upset, sedation
Serious Adverse Effects: Depression, suicidal ideation (due to CNS catecholamine depletion)
Contraindications: History of depression, peptic ulcer
Therapeutic Considerations: Depletes NE, dopamine, serotonin in both CNS and PNS; long-lasting effects
Drug: Guanethidine
(Adrenergic)
Class: Adrenergic neuron blocker
Clinical Applications: Rarely used antihypertensive
Common Side Effects: Orthostatic hypotension, diarrhea, sexual dysfunction
Serious Adverse Effects: Bradycardia, fluid retention
Contraindications: MAOI therapy, pheochromocytoma
Therapeutic Considerations: Replaces NE in nerve terminals and inhibits NE release; slow onset of action
Drug: Midodrine
(Adrenergic)
Class: Alpha-1 agonist (prodrug)
Clinical Applications: Orthostatic hypotension Common
Side Effects: Paresthesia, piloerection, urinary retention
Serious Adverse Effects: Supine hypertension
Contraindications: Severe heart disease, urinary retention
Therapeutic Considerations: Converted to active form (desglymidodrine); avoid dosing near bedtime to prevent nocturnal hypertension
Drug: Clonidine
(Adrenergic)
Class: Alpha-2 adrenergic receptor agonist
Clinical Applications: Hypertension, ADHD, withdrawal symptoms
Common Side Effects: Dry mouth, sedation, dizziness
Serious Adverse Effects: Rebound hypertension on sudden withdrawal
Contraindications: Bradyarrhythmia, severe coronary insufficiency
Therapeutic Considerations: Decreases sympathetic outflow from CNS; taper gradually to avoid rebound hypertension
Drug: Dobutamine
(Adrenergic)
Class: Beta-1 adrenergic receptor agonist
Clinical Applications: Acute heart failure, cardiogenic shock
Common Side Effects: Tachycardia, hypertension, palpitations
Serious Adverse Effects: Arrhythmias
Contraindications: Idiopathic hypertrophic subaortic stenosis
Therapeutic Considerations: Increases contractility and output more than heart rate; short-term IV use only
Drug: Albuterol
(Adrenergic)
Class: Beta-2 adrenergic receptor agonist
Clinical Applications: Acute bronchospasm (asthma, COPD), bronchodilator
Common Side Effects: Tremor, nervousness, tachycardia
Serious Adverse Effects: Paradoxical bronchospasm, arrhythmias
Contraindications: Hypersensitivity to albuterol or excipients
Therapeutic Considerations: Rapid onset, short-acting; overuse may cause receptor desensitization
Drug: Amphetamine
(Adrenergic)
Class: Indirect-acting sympathomimetic
Clinical Applications: ADHD, narcolepsy
Common Side Effects: Insomnia, anorexia, increased BP
Serious Adverse Effects: Dependence, psychosis, cardiovascular events
Contraindications: Cardiovascular disease, hypertension, hyperthyroidism
Therapeutic Considerations: Increases release of NE and dopamine from nerve terminals; CNS stimulant
Drug: Pseudoephedrine
(Adrenergic)
Class: Mixed-acting sympathomimetic
Clinical Applications: Nasal congestion
Common Side Effects: Insomnia, anxiety, hypertension
Serious Adverse Effects: Tachycardia, stroke (rare)
Contraindications: Severe hypertension, MAOI use
Therapeutic Considerations: Direct agonist at α and β receptors and promotes NE release; less CNS stimulation than amphetamines
Drug: Phenylephrine
(Adrenergic)
Class: Alpha-1 adrenergic receptor agonist
Clinical Applications: Nasal congestion, hypotension, pupil dilation
Common Side Effects: Hypertension, reflex bradycardia
Serious Adverse Effects: Arrhythmias, rebound congestion (nasal)
Contraindications: Severe hypertension, ventricular tachycardia
Therapeutic Considerations: Used topically or IV; avoid prolonged use in nasal sprays to prevent rebound effect
Drug: Tyramine
(Adrenergic)
Class: Indirect sympathomimetic (naturally occurring amine)
Clinical Applications: No therapeutic use; relevance in food-drug interactions
Common Side Effects: None under normal metabolism
Serious Adverse Effects: Hypertensive crisis (with MAOIs)
Contraindications: Use with MAO inhibitors
Therapeutic Considerations: Found in fermented foods; releases NE from adrenergic terminals; degraded by MAO under normal conditions
Drug: Cocaine
(Adrenergic)
Class: Monoamine reuptake inhibitor
Clinical Applications: Local anesthesia (ENT procedures); vasoconstriction
Common Side Effects: Euphoria, tachycardia, insomnia
Serious Adverse Effects: Seizures, arrhythmias, myocardial infarction
Contraindications: Cardiovascular disease, concurrent sympathomimetic use
Therapeutic Considerations: Inhibits reuptake of NE, dopamine, serotonin; significant abuse potential and toxicity. It increases sympathetic activity
Drug: Phentolamine
(Adrenergic)
Class: Non-selective alpha-adrenergic receptor antagonist
Clinical Applications: Pheochromocytoma (diagnosis and management), hypertensive emergencies due to catecholamines
Common Side Effects: Hypotension, reflex tachycardia
Serious Adverse Effects: Arrhythmias, myocardial ischemia
Contraindications: Coronary artery disease
Therapeutic Considerations: Short-acting; used in surgery or catecholamine excess
Drug: Prazosin
(Adrenergic)
Class: Selective alpha-1 adrenergic receptor antagonist
Clinical Applications: Hypertension, benign prostatic hyperplasia (BPH)
Common Side Effects: Dizziness, orthostatic hypotension, headache
Serious Adverse Effects: Syncope (especially first dose)
Contraindications: Hypersensitivity
Therapeutic Considerations: “First-dose effect” — start with low dose at bedtime
Drug: Tamsulosin
(Adrenergic)
Class: Alpha-1A adrenergic receptor antagonist
Clinical Applications: BPH (urinary retention)
Common Side Effects: Dizziness, abnormal ejaculation
Serious Adverse Effects: Hypotension (less than with prazosin)
Contraindications: Known hypersensitivity
Therapeutic Considerations: Selective for prostate/bladder neck; minimal BP effects
Drug: Labetalol & Carvedilol
(Adrenergic)
Class: Mixed alpha-1 and beta adrenergic receptor antagonists
Clinical Applications: Hypertensive emergencies (labetalol), heart failure and hypertension (carvedilol)
Common Side Effects: Fatigue, dizziness, orthostatic hypotension
Serious Adverse Effects: Bradycardia, bronchospasm
Contraindications: Asthma, AV block, bradycardia
Therapeutic Considerations: Dual blockade reduces BP without reflex tachycardia; carvedilol has antioxidant properties
Drug: Propranolol
(Adrenergic)
Class: Non-selective beta adrenergic receptor antagonist
Clinical Applications: Hypertension, angina, arrhythmias, migraine prophylaxis
Common Side Effects: Fatigue, cold extremities, bradycardia
Serious Adverse Effects: Bronchospasm, depression, heart block
Contraindications: Asthma, severe bradycardia
Therapeutic Considerations: Crosses BBB; not selective, affects β1 and β2 equally
Drug: Atenolol
(Adrenergic)
Class: Beta-1 selective adrenergic receptor antagonist
Clinical Applications: Hypertension, angina, post-MI
Common Side Effects: Fatigue, dizziness
Serious Adverse Effects: Bradycardia, AV block
Contraindications: Sinus bradycardia, AV block
Therapeutic Considerations: Less CNS penetration than propranolol; preferred in patients with asthma or COPD