Drugs Acting on Autonomic Nervous System (ANS)

10/01/2025
4 min read

A. Drugs for Cholinergic System:

  1. Cholinergic agents:
    • Directly acting:
      • Choline esters: Acetylcholine, bethanechol, carbachol
      • Alkaloids: Pilocarpine, muscarine
    • Indirectly acting: (Anticholinesterases)
      • Reversible:
        • Carbamates: Physostigmine, Neostigmine, Pyridostigmine, Rivastigmine
        • Alcohols: Edrophonium
        • Others: Donepezil, galantamine, tacrine
      • Irreversible:
        • Organophosphorous compounds: Parathion, Malathion, Sarin, soman, tabun (nerve gases), Dyflos, Echothiophat
        • Carbamates: Propoxur, carbaryl
  2. Anticholinergic agents:
    • Natural alkaloids:
      Atropine, hyoscine (scopolamine)
    • Semisynthetic derivatives:
      Atropine methonitrate, homatropine, hyoscine butylbromide, Ipratropium bromide, tiotropium bromide
    • Synthetic compounds:
      • Antisecretory-antispasmodics:
        • Quaternary compounds: Propantheline, oxyphenonium, clidinium, pipenzolate methyl bromide, isopropamide
        • Teritiary amines: Dicyclomine, valethamate, pirenzepine
      • Mydriactics: Cyclopentolate, tropicamide
      • Vasicoselective: Oxybutynin, flavoxate, tolterodine
      • Antiparkinsonian: Trihexyphenidyl (Benzhexol), procyclidine, biperidin

B. Drugs for Adrenergic System:

  1. Adrenergic Agonists: (sympathomimetics)
    • Pressor agents: Noradrenaline(Norepinephrine), Ephedrine, Dopamine, Phenylephrine, Methoxamine, Mephentermine
    • Bronchodilators: Isoprenaline, Salbutamol (Albuterol), Terbutaline, Salmeterol, Formoterol, Bambuterol
    • CNS stimulants: Amphetamine, Dexamphetamine, Methamphetamine, Methylphenidate
    • Uterine relaxants: Ritodrine, Isoxsuprine Salbutamol, Terbutaline
    • Cardiac stimulants: Adrenaline, Isoprenaline, Dobutamine
    • Nasal decongesants: Xylometazoline, Oxymetazoline, Naphazoline, Phenylephrine, Phenylpropanolamine, Pseudoephedrine
    • Anorectics:
      Amphetamine, Fenfluramine, sibutramine
  2. Adrenergic receptor blockers:
    • α Adrenergic blocking drugs:
      • Non equilibrium type:
        • β-haloalkylamine: Phenoxybezamine
      • Equilibrium type:
        • Non selective:
          • Ergot alkaloids: Ergotamine, Ergotoxine
          • Imidazoline: Phentolamine
          • Hydrogenated ergot alkaloids: Dihydroergotamine (DHE), Dihydroergotoxine (Codergocrine)
          • Miscellaneous: Chlorpromazine
        • α1 Selective: Prazosin, Terazosin, Doxazosin, Alfuzosin, Tamsulosin
        • α2 Selective: Yohimbine
    • β Adrenergic blocking drugs:
      • First Classification:
        • Non selective (β1 + β2):
          • With Intrinsic sympathetomimetic activity (ISA): Pindolol
          • Without ISA: Propranolol, Sotalol, Timolol
          • With α blocking property: Labetalol, Carvedilol
        • Cardioselective (β1): Metoprolol, Atenolol, Acebutolol, Bisoprolol, Esmolol, Betaxolol, Celiprolol, Nebivolol
      • Second Classification:
        • First generation:

          (Older, nonselective)

          Timolol, Betaxolol, Levobunolol, Carteolol
        • Second generation:

          1 or cardioselective)

          Metoprolol, Atenolol, Acebutolol, Bisoprolol, Esmolol
        • Third generation:

          (With α blocking and or vasodilator property)

          Labetalol, Carvedilol, Celiprolol, Nebivolol, Betaxolol
Topical Drugs for Glaucoma:
  1. β-Adrenergic agonists: Timolol, Betaxolol, Levobunolol, Carteolol
  2. α-Adrenergic agonists: Dipivefrine, Apraclonidine, Brimonidine
  3. prostaglandin analogues: Latanoprost, Travoprost, Bimatoprost
  4. Carbomic anhydrase inhibitors: Dorzolamide, Brinzolamide
  5. Miotics: Pilocarpine, Physostigmine, Echothiophate