Atropine

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Revision as of 04:26, 24 October 2008

Pronouncation: (AT-troe-peen) Class: Belladonna alkaloid, Cycloplegic mydriatic

Trade Names: AtroPen - Injection 0.5 mg - Injection 1 mg - Injection 2 mg

Trade Names: Atropine Sulfate - Ophthalmic solution 1% - Injection 0.05 mg/mL - Injection 0.1 mg/mL - Injection 0.4 mg/mL - Injection 0.8 mg/mL - Injection 1 mg/mL

Trade Names: Atropine Sulfate Ophthalmic - Ointment 1%

Trade Names: Isopto Atropine - Ophthalmic solution 1%

Trade Names: Sal-Tropine - Tablets 0.4 mg Atropine (Canada) Atropine Injection (Canada) Atropine Ointment (Canada) Minims Atropine (Canada)

Pharmacology

Inhibits action of acetylcholine or other cholinergic stimuli at postganglionic cholinergic receptors, including smooth muscles, secretory glands, and CNS sites.

Pharmacokinetics

Absorption - Rapidly absorbed after oral administration.

Distribution - Readily crosses blood-brain barrier.

Elimination - The t ½ is 3 h (IV). 94% of dose is eliminated through urine in 24 h.

Indications and Usage

Administration prior to anesthesia to reduce or prevent secretions of respiratory tract; to control rhinorrhea; treatment of parkinsonism; restoration of cardiac rate and arterial pressure in some situations; treatment of peptic ulcers; management of hypersecretion, irritation, or inflammation of stomach, intestines, or pancreas; treatment of diarrhea; relief of infant colic; management of spasms of bile tract; treatment of hypertonicity of small intestine and uterus; management of hypermotility of colon; prevention of spasm of pylorus, biliary tree, ureters, and bronchi; treatment of frequent urination and bed-wetting; therapy for certain bradycardias and heart blocks; treatment of closed head injury with acetylcholine release; reduction of laughing and crying associated with brain lesions; treatment of alcohol withdrawal symptoms; relief of motion sickness. Antidote for CV collapse in certain overdoses or poisonings (eg, organophosphorous nerve agents having cholinesterase activity, organophosphorous or carbamate insecticides, muscarinic symptoms of insecticide or nerve agent poisonings). Short-term treatment and prevention of bronchospasm associated with chronic bronchial asthma, bronchitis, and COPD.

Ophthalmic - Production of cycloplegia and mydriasis.

Contraindications

In the face of life-threatening poisonings by organophosphorous nerve agents and insecticides, there are no absolute contraindications for atropine use. Hypersensitivity to anticholinergics; narrow-angle glaucoma; primary glaucoma or tendency toward glaucoma (ophthalmic); adhesions between iris and lens; prostatic hypertrophy; obstructive uropathy; myocardial ischemia; unstable cardiac status caused by hemorrhage; tachycardia; myasthenia gravis; pyloric or intestinal obstruction; asthma; hyperthyroidism; renal disease; hepatic disease; toxic megacolon; intestinal atony or paralytic ileus.

Dosage and Administration

Adults - 0.4 to 0.6 mg every 4 to 6 h.

Children - PO Use lowest effective dose. The following doses may be exceeded in certain cases: 7 to 16 lb: 0.1 mg; 17 to 24 lb: 0.15 mg; 24 to 40 lb: 0.2 mg; 40 to 65 lb: 0.3 mg; 65 to 90 lb: 0.4 mg; over 90 lb: 0.4 mg.

Surgery

Adults - Subcutaneous/IM/IV 0.4 to 0.6 mg every 4 to 6ߙh. Children - Subcutaneous/IM/IV 0.01 mg/kg to max of 0.4 mg every 4 to 6 h.

Infants less than 5ߙkg

Subcutaneous/IM/IV 0.04ߙmg/kg.

Infants over 5ߙkg

Subcutaneous/IM/IV 0.03 mg/kg.

Bradyarrhythmias

Adults - Subcutaneous/IM/IV 0.4 to 2 mg every 1 to 2 h as needed.

Children - Subcutaneous/IV/IM 0.01 to 0.03 mg/kg, every 1 to 2 h as needed. Antidote (Insecticide Poisoning)

Adults - Parenteral At least 2 to 3 mg, repeated until signs of poisoning subside or signs of intoxication appear.

Children - 0.02 to 0.05 mg/kg/dose every 10 to 20 min until signs of atropic effect are observed, then every 1 to 4 h for at least 24 h. AtroPen

It is recommended that 3 AtroPen auto-injectors be available for use in each person at risk of nerve agent or organophosphate insecticide poisoning: 1 for mild symptoms plus 2 for severe symptoms as described in package insert.

Adults and Children weighing over 90 lb (41 kg) (generally older than 10 yr of age)

IM 2 mg. Children weighing 40 to 90 lb (18 to 41 kg) (generally 4 to 10 yr of age)

IM 1 mg. Children weighing 15 to 40 lb (7 to 18 kg) (generally 6 mo to 4 yr of age)

IM 0.5 mg. Children weighing less than 15 lb (7 kg) (generally younger than 6 mo of age)

IM 0.25 mg.

Ophthalmic

Uveitis Adults - 1 to 2 drops 0.5% to 1% solution up to 4 times daily or ointment once or twice daily.

Children - 1 to 2 drops 0.5% solution 3 times daily.

Refraction

Adults - 1 to 2 drops of 1% solution 1 h before refraction examination.

Children - 1 to 2 drops 0.5% solution twice daily 1 to 3 days before refraction examination.

General Advice

• Multiple concentrations are available for use. Carefully check concentration before administering medication to ensure that proper strength is being used.

• Inspect injection solution before administration. Do not administer if solution is discolored, cloudy, or if particulate matter noted.

• Use auto-injector as soon as symptoms of organophosphorous or carbamate poisoning (eg, tearing, excessive oral secretions, wheezing, muscle fasciculations) appear. Use additional auto-injectors as needed, but no more than 3 units unless under supervision of trained medical personnel, until atropinization (eg, flushing, mydriasis, tachycardia, dry mouth) is achieved.

• Administer as IM injection into patient's mid-lateral thigh.

Storage/Stability

Tablets - Store at temperature below 86°F.

Ophthalmic - Store at room temperature (less than 86°F). Protect from heat.

Injection - Store vials, prefilled syringes, and auto-injector at controlled room temperature (68° to 77°F). Protect from light and freezing.