Pilocarpine hydrochloride (solution 1% (eye drops)
Solutio Pilocarpini hydrochloridi 1% (guttae ophthalmicae)
International unlicensed name
Pilocarpine.
Pharmacotherapy group
Antiglaucoma preparation, miotics. Parasympathomimetic agents.
Composition
1 ml of sterile solution (eye drops) contains 10 mg of policarpine hydrochloride.
Pharmacological action
Pharmacodynamics
Pilocarpine stimulates flat muscle muscarine receptors, comprising the iris and glands — peptic, bronchial, external secretion (salivary, sweat, etc.). It induces contraction of circular (mios) and ciliary (spasm accommodation) muscle.
In case of angle-closure glaucoma it narrows the pupil, induces the iris displacement from the frontal chamber angle and provides opening of Schlemm canals and Fontana’s spaces.
In patients with angle-open glaucoma it also opens Schlemm canals and trabecular fissues and increases ciliary muscle tonus.
In case of primary angle-open glaucoma or eye hypertension, single instillation of 1% solution induces intraocular tension at 25—26%. The action starts after 30—40 minutes, and its maximum is achieved after 1,5—2 hour and lasts 4—8 hours.
Indication
Glaucoma, comprising acute form; eye trophism disturbance on thrombosis of the retina central vein or acute artery impassability, on visual nerve atrophy, hemorrhage into vitreous body; elimination of atropine mydriatic action, homatropine, scopolamine.
Route and dosage
The preparation shall be instilled into the conjunctival sac 1—2 drops 2—3—4 times a day.
Special indications
The pilocardine may cause decrement in visual acuity therefore it shall be prescribed with care to drivers and persons carrying out potentially dangerous activities requiring visual acuity, high concentration and quick reaction.
Side effects
Headache in the temporal and periorbital zones, pain in the eye, myopia, spasm accommodation, blurring, decrement in twilight vision, watering, rhinorrhea, follicular conjunctivitis, superficial keratitis,contact eyelid dermatitis (rarely).
Contraindications
Iritis, iridocyclitis and other eye diseases for which miosis is undesirable, hypersensitivity, bronchial asthma excerbation, condition after ophthalmologic operations, high-stage myopia with risk of retina detachment, angle-close glaucoma, pregnancy, lactation (breast-breeding shall be ceased). It is not used in children, teenagers and the juvenile (up to 18 years old).
Precautions
The treatment shall be carried out on a regular monitoring of intraocular pressure. To decrease the absorption after instillation it is recommended to pinch the lachrymal canal pressing the internal eye angle with finger.
Interaction with other medications
Antagonists of pilocarpine hydrochloride are antropin and other М-cholinolytic agents. Timolol maleate and mezaton reduces intraocular pressure. Side effects of beta-adrenoblockers are possible (marked bradycardia, intracardial conductivity). М-cholinoceptive activity is decreased by tricyclic antudepressants, phenothiazine derivatives, chlorprothixene, clozapin. It is increased by anticholinesterase preparations. Development of bradycardia and hypotension is possible on halothane hypnosis in patients using pilocarpine in eye drops.
Overdosing
On overdosing and high sensitivity excessive salivation, sweating, bradycardia, blood pressure drop are possible. On oral administration poisoning is possible that induces m-cholinoceptive effects, among them – development of serious heart failure and bronchocontriction.
Treatment: stomach lavage, monitoring of heart rate, blood pressure, respiratory function, atropine administration (0,5—1,0 mg i/v or s/c), epinephrine (0,3—1,0 mg i/v or s/c), as well as drinking a lot of liquidr.
Product form
1 ml of sterile solution (eye drops) contains 10 mg of policarpine in 1 ml. In 1 ml drop tube (2 or 10 drop tubes per package).
