Autonomic drugs and glaucoma drugs Flashcards
Direct Acting Muscarinic Drugs
Betanechol, Pilocarpine
MOA: Inhibits M3 receptors
Indirect Acting Nicotinic Drugs
Nicotine and Varenicline
Drugs used in Alzheimer’s Disease
Rivastigmine, Donepazil, Tacrine, Galantamine
Drug used in bowel and bladder atony
Betanechol
Indirect acting muscarinic receptor used for treatment of glaucoma
Physostigmine
Antidotes for organophosphate poisoning
Atropine Pralidoxime (should be given only within 6 hours)
Nonselective Cholinergic Antagonist
Atropine, Tropicamide, Homatropine, Cyclopentolate
Nonselective Cholinergic antagonist used in the treatment of Parkinsons disease
Benztropine, Biperiden, Trihexyphenidyl
Cholinergic antagonist used in the treatment of asthma
Ipatropium and tiotropium
Side effect: Nasal dryness
Why Ipatropium and tiotropium preferred as bronchodilators for combined COPD and heart disease patients?
less likely to cause tachycardia and cardiac arrhythmias
Nonselective muscarinic antagonist used in the treatment of motion sickness
Scopolamine (has an additional histamine and serotonin antagonistic effect)
Symptoms of atropine toxicity
Hot as a hare (hyperthermia)
Dry as a bone (decreased secretions and constipation)
Red as a a beet (atropine flush)
Blind as a bat (blurred vision)
Mad as a hatter (CNS toxicity, tachycardia, arrhythmia)
Cholinergic antagonist that blocks Nicotinic AcH receptors (ganglion blockers) used in the treatment of hypertension? Side effect?
Hexamethonium, Trimethaphan
Side effect: Postural Hypertension
What is the difference of dopamine and norepinephrine in their action in the blood vessels?
Dopamine: vasodilates the renal blood vessels
Norepinephrine: vasoconstricts the renal blood vessels
Inhibitor of tyrosine hydroxylase
Metyrosine - prevents conversion of tyrosine to DOPA
Vesicular transport of norepinephrine and epinephrine is inhibited by what drug
Reserpine
MAO’s increase stores of norepinephrine and epineprhine
What drug inhibits entry of calcium which triggers interaction among SNARE proteins (VAMPs and SNAPS? What drugs promote them?
Inhibited by Guanethidine
Promoted by Amphetamines and Tyramine
Diffusion and reuptake of norepi and epi via NET and DAT in the synaptic cleft is inihibited by what drugs?
Cocaine and TCA
MOA of Epinephrine
Nonselective and Direct acting Sympathomimetic (activates alpha and beta)
a1: vasoconstriction, increases BP
b1: increases heart rate, conduction and contractility (cardiac arrest)
b2: bronchodilation (anaphylaxis)
Uses and side effects of norepinephrine
Neurogenic shock, cardiogenic shock (last resort)
Extreme vasospasm, tissue necrosis and extensive blood pressure increase
Dose dependent actions of dopamine
Low dose: 1 - 5 mcg/kg/min - vasodilation of the splanchnic and renal vascular beds via D1 receptors (thus increase in renal blood flow)
Medium Dose: 5-15 mcg/kg/min - D1 and B2 receptors
High dose: >15 mcg/kg/min - A1 receptors
Beta nonselective sympathomimetic drug that is used in the treatment of asthma?
Isoproterenol
B1: increases heart rate, conduction and velocity
B2: bronchodilation
SE: cardiovascular disturbance, arrhythmias
Selective alpha 1 agonist used as decongestant? Side effect?
Phenylephrine, Pseudoephrine
SE: rebound nasal congestion
Ocular administration may cause mydriasis without cyclopegia
Selective alpha 2 agonist (decreases central sympathetic outflow)? Side effect?
Clonidine
SE: rebound hypertension - Treated using Phentolamine
Selective alpha 2 agonist used in the treatment of hypertension which causes hemolytic anemia?
Methyldopa
Selective alpha 2 agonist used in the treatment of glaucoma (decreases secretion of aqueous humor)?
Apraclonidine, Brimonidine
Selective beta 1 agonist used in acute heart failure and cardiogenic shock? Side effect?
Dobutamine
Side effect: tachyphylaxis
Other uses: Used in cardiac stress testing
Selective beta 2 agonists used in the treatment of asthma
Albuterol/Salbutamol
Terbutaline and Ritodrine
Selective beta 2 agonists used as tocolytic in preterm labor
terbutaline and ritodrine
Remember: beta 2 receptors - relaxation of uterine muscles vs alpha 1 and M3 receptors which causes contraction of uterine muscles
Drugs used in the presurgical treatment of hypertension in pheochromocytoma?
Phenoxybenzamine and Phentolamine
MOA: nonselective alpha blockers (alpha 1>alpha2)
SE: Orthostatic hypotension
Difference between phenoxybenzamine and phentolamine
Phenoxybenzamine: IRREVERSIBLE Inhibitor
Phentolamine: REVERSIBLE Inhibitor, can also be used as treatment for rebound hypertension (e.g. Clonidine)
Selective alpha 1 receptors used in the treatment of benign prostatic hyperplasia and hypertension?
Prazosin, Doxazosin, Terazosin, Tamsulosin, Silodosi
Side effect: First dose orthostatic hypotension
Most selective for prostatic smooth muscle?
Tamsulosin
Nonselective beta blockers
Propranolol, Pindolol, Timolol, Labetalol, Carvedilol, Nadolol
SE: bronchospasm, erectile dysfunction
Drug which has a combined alpha and beta blocker blockade (can also be used in the treatment of pheochromocytoma)
Labetalol
Nonselective beta blockers which has an intrinsic sympathomimetic activity
Pindolol and acebutolol
Beta blocker which has an absent Local anesthetic activity
timolol and betaxolol
(local anesthetic activity is disadvantageous when used in the eye topically since it can decrease protective effects and increase the risk of corneal ulcerations)
Beta blocker which has the longest half-life
Nadolol
selective beta blockers
Betaxolol, esmolol, acebutolol, atenolol, and metoprolol
Selective beta blockers used for supraventricular tachycardia
Esmolol
Beta blocker which has the shortest half-life
Esmolol
Flow of aqueous humor
Ciliary body - Posterior chamber - Angle of the anterior chamber - Pupil - Anterior chamber - trabecular meshwork - canal of schlemm - Uveoscleral veins
Drugs that cause decreased secretion of aqueous humor from the ciliary epithelium
Beta blocker: Timolol
Osmotic agents: Mannitol
Alpha2 agonist: Apraclonidine
Carbonic Anhydrase Inhibitor: acetazolamide, dorzolamide
Drugs that cause ciliary muscle contraction, opening of trabecular meshwork and increased outflow through canal of schlemm
Cholanomimetics: Pilocarpine, Physostigmine
Drugs that cause increased outflow through canal of Schlemm
Prostaglandins: latanoprost
Drugs that causes increased outflow via uveoscleral veins
Epinephrine
