Monograph: |
Acetylcholine Chloride
DESCRIPTION:
Acetylcholine chloride is a parasympathomimetic preparation for intraocular use packaged in a vial of two compartments; the lower chamber containing acetylcholine chloride 20 mg and mannitol 60 mg; the upper chamber containing sterile water for injection 2 ml.
The reconstituted liquid will be a sterile isotonic solution containing 20 mg acetylcholine chloride (1:100 solution) and 3% mannitol. Mannitol is used in the process of lyophilizing acetylcholine chloride, and is not considered an active ingredient.
The chemical name for acetylcholine chloride, C7H16CINO2, is 2-acetoxyethyltrimethylammonium chloride.
CLINICAL PHARMACOLOGY:
Acetylcholine is a naturally occurring neurohormone which mediates nerve impulse transmission at all cholinergic sites involving somatic and autonomic nerves. After release from the nerve ending, acetylcholine is rapidly inactivated by the enzyme acetylcholinesterase by hydrolysis to acetic acid and choline.
Direct application of acetylcholine to the iris will cause rapid miosis of short duration. Topical ocular instillation of acetylcholine to the intact eye causes no discernible response as cholinesterase destroys the molecule more rapidly than it can penetrate the cornea.
INDICATIONS AND USAGE:
To obtain complete miosis of the iris in seconds after delivery of the lens in cataract surgery, in penetrating keratoplasty, iridectomy and other anterior segment surgery where rapid, complete miosis may be required.
CONTRAINDICATIONS:
There are presently no known contraindications to the use of acetylcholine intraocular.
WARNINGS:
If blister or peelable backing is damaged or broken, sterility of the enclosed bottle cannot be assured. Open under aseptic conditions only.
WARNING: DO NOT GAS STERILIZE
PRECAUTIONS:
If miosis is to be obtained quickly and completely with acetylcholine, obstructions to miosis, such as anterior or posterior synechiae, may require surgery prior to administration of acetylcholine. In cataract surgery, use acetylcholine only after delivery of the lens. NOTE: Aqueous solutions of acetylcholine chloride are unstable. Prepare solution immediately before use. Do not use solution which is not clear and colorless. Discard any solution that has not been used.
Pediatric Use: Safety and effectiveness in children have not been established.
DRUG INTERACTIONS:
Although clinical studies with acetylcholine chloride and animal studies with acetylcholine or carbachol revealed no interference, and there is no known pharmacological basis for an interaction, there have been reports that acetylcholine chloride and carbachol have been ineffective when used in patients treated with topical nonsteroidal anti-inflammatory agents.
ADVERSE REACTIONS:
Infrequent cases of corneal edema, corneal clouding, and corneal decompensation have been reported with the use of acetylcholine.
Adverse reactions have been reported rarely which are indicative of systemic absorption. These include bradycardia, hypotension, flushing, breathing difficulties and sweating.
OVERDOSAGE:
Atropine sulfate (0.5 to 1 mg) should be given intramuscularly or intravenously and should be readily available to counteract possible overdosage. Epinephrine (0.1 to 1 mg subcutaneously) is also of value in overcoming severe cardiovascular or bronchoconstrictor responses.
DOSAGE AND ADMINISTRATION:
With a new needle of sturdy gauge, 18-20, draw all of the solution into a dry, sterile syringe. Replace needle with a suitable atraumatic cannula for intraocular irrigation.
The acetylcholine solution is instilled into the anterior chamber before or after securing one or more sutures. Instillation should be gentle and parallel to the iris face and tangential to pupil border.
If there are no mechanical hindrances, the pupil is rapidly constricted and the peripheral iris drawn away from the angle of the anterior chamber. Any anatomical hindrance to miosis may require surgery to permit the desired effect of the drug. In most cases, 1/2 to 2 ml produces satisfactory miosis. The acetylcholine solution need not be flushed from the chamber after miosis occurs. Since the action of acetylcholine is of short duration, pilocarpine may be applied topically before dressing to maintain miosis.
In cataract surgery, use acetylcholine only after delivery of the lens.
NOTE: Aqueous solutions of acetylcholine chloride are unstable. Prepare solution immediately before use. Do not use solution which is not clear and colorless. Discard any solution that has not been used.
Directions For Using The Univial: Sterile Unless Package Open Or Broken
1. Inspect univial while inside unopened blister. Diluent must be in upper chamber. 2. Peel open blister. 3. Aseptically transfer univial to sterile field. Maintain sterility of outer container during preparation of solution. 4. Immediately before use, give plunger-stopper a quarter turn and press to force diluent and center plug into lower chamber. 5. Shake gently to dissolve drug. 6. Discard univial and any unused solution.
Keep From Freezing: Store at 15Β°-30Β°C (59Β°-86Β°F).
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