Proxymethacaine - instructions for use, dose, side effects, contraindications

Clinical and pharmacological group: & nbsp

Local Anesthetics

Included in the formulation

Alkain®

drops d / eye

ALKON PHARMACEUTICS, LLC Russia

АТХ:

S.01.H.A Local Anesthetics

S.01.H.A.04 Proxymethacaine

Pharmacodynamics:

It disrupts generation and conduction of nerve impulses mainly in non-mielin fibers. Local anesthetic (weak base) in non-ionized form (blood pH 7.4) penetrates through the cell membrane into the axon and ionizes there. Ionized molecules of matter interact with specific sites of binding of sodium channels from the inside of the membrane and, blocking sodium channels, interfere with Na + entry into the cell and depolarize the membrane. As a result, the generation of the action potential and the propagation of impulses along the nerve fiber are violated. Local anesthetics have an affinity for the sodium channel, which is in the inactivated state (potential-dependent sodium channels have three states: rest - closed, activation - open and inactivated - closed). Thus, local anesthetics block the passage of these channels into an open state.

Pharmacokinetics:After instillation into the eye, it is rapidly absorbed through the conjunctival capillaries. It is hydrolyzed by plasma esterases, excreted by the kidneys in the form of inactive cleavage products.With a single instillation, the anesthetic effect is manifested after 30 seconds and remains for at least 15 minutes.

Indications:Local anesthesia in ophthalmology for diagnostic and treatment procedures requiring fast and short-term anesthesia: surgical intervention for cataracts, surgeries for suture removal from the cornea or conjunctiva; tonometry, gonioscopy; removal of a foreign body from the cornea; diagnostic scrapings with conjunctiva.

ICD-10

VII.H10-H13.H11.9 Disease of conjunctiva, unspecified

VII.H15-H22.H18.9 Corneal disease, unspecified

VII.H25-H28.H26.9 Cataract, unspecified

XX.Y40-Y59.Y57.6 Other diagnostic drugs

XXI.Z00-Z13.Z01.0 Examination of eyes and eyesight

XXI.Z40-Z54.Z40 Prophylactic surgical intervention

Contraindications:Hypersensitivitytion.

Carefully:

Assign with caution to patients with allergic reactions, epilepsy, heart disease, hyperthyroidism and breathing disorders; patients with myasthenia gravis, patients with low acetylcholinesterase in plasma, as well as patients undergoing treatment with cholinesterase inhibitors (because they are more at risk of systemic adverse reactions).

Pregnancy, breast-feeding, children's age (safety and effectiveness of use in children are not defined).

Pregnancy and lactation:

Recommendations FDA category C. Studies of the teratogenicity of proximetacaine have not been conducted, complications have not been documented.

When pregnancy is possible, if the expected effect of the application exceeds the potential risk to the fetus.

There is no information on the penetration into breast milk, but the negative impact on the child is not described. With caution in the period of breastfeeding!

Dosing and Administration:

Locally. Deep anesthesia with cataract removal: instill in the eye 1-2 drops every 5-10 minutes (3-5 doses). When removing stitches: 1-2 drops every 5-10 minutes (1-3 times). Removal of foreign matter: 1-2 drops before removal. Tonometry: 1-2 drops immediately before measurement.

Doses for children correspond to those for adults.

Side effects:

After instillation in the eyes, there may be a temporary burning sensation and redness; very rarely: severe allergic reactions (diffuse epithelial keratitis, necrosis of the epithelium, diffuse edema of the stroma, iritis).

Lachrymation, increased blinking - after instillation, sometimes signs of local irritation or increased blinking may appear a few hours after instillation; allergic reactions, incl.contact (dermatitis, dryness and skin cracks at the fingertips), pupil dilated, cycloplegic effects, edema and erosion of the corneal epithelium, conjunctival hemorrhage.

With prolonged use - infection and / or opacity of the cornea, prolonged loss of vision; perforation of the cornea.

Systemic intoxication (0.01-0.1%) - is manifested by CNS excitation with its subsequent inhibition.

Overdose:

Clinical manifestations of systemic toxicity: apnea, collapse (decreased blood pressure, rare or irregular pulse, pallor, sweating, cardiac arrest possible), methemoglobinemia, central neurotoxicity (double vision, confusion, convulsions, dizziness, ringing or buzzing in the ears, trembling, irritability, agitation, nervousness , stimulation, and then depression of the central nervous system, as well as loss of consciousness and respiratory arrest are possible).

Treatment: with topical application - removal from the skin and mucous membranes; at a collapse - infusion therapy and application of vasopressors. In case of hypotension, the woman in labor should be placed on her left side in order to eliminate the pressure of the pregnant uterus on the aorta and inferior vena cava; Delivery can improve the response to ongoing activities.When convulsions are necessary to ensure the safety of the patient and the supply of oxygen; in the absence of the effect of respiratory support - iv injection of benzodiazepines (diazepam with an increment of 2.5 mg) or barbiturates of ultrashort action (sodium thiopental, thiamylal with an increment of 50-100 mg, with / in the introduction of barbiturates may inhibition of hemocirculation) with an interval of 2- 3 min; with nekupiruemyh convulsions and the presence of mechanical ventilation are shown muscle relaxants; In a short time after the onset of seizures, hypoxia, hypercapnia and acidosis can quickly develop; monitoring of blood pressure, heart rate, neurological status and respiratory function is continuous. Supportive therapy: providing and maintaining airway patency, if necessary - endotracheal intubation, IVL. With methemoglobinemia: in the absence of response to oxygen recommended the administration of methylene blue (IV for 5 minutes 1-2 mg / kg as a 1% solution).

Interaction:Data on the interaction of proximetacaine with other drugs are absent.

Special instructions:

Long-term toxic effects are currently unknown. With prolonged use, it is possible to slow the healing of ophthalmic lesions.

Long-term animal studies to assess potential carcinogenic and mutagenic effects, effects on reproductive function and fertility have not been carried out.

Proxymethacaine is not recommended for prolonged or repeated intraocular use in order to avoid severe damage to the cornea: cases of severe keratitis, clouding, and scarring of the cornea with loss of vision are described.

It is necessary to correlate the potential risks and benefits of using proximethacaine in inflammation and / or eye infections, as changing local pH and / or increasing blood circulation can reduce or eliminate the effect of local anesthetics.

Use in ophthalmology: during anesthesia with proximetacaine, it is necessary to protect the eye from friction and ingress of aggressive chemicals, foreign bodies (it is necessary to cover the eye with a bandage), since the blinking reflex is temporarily suppressed; rubbing or touching the tissues of the eye during anesthesia can damage the corneal epithelium and conjunctiva; in the case of anesthesia with proximetacaine in tonometry before manipulation, it is necessary to rinse the tonometer with sterile distilled water to remove the remains of sterilizing and washing solutions.For the treatment of local allergic reactions, glucocorticoids and antihistamines for ophthalmic use are used.

There is no evidence to limit the use of this drug in childhood and in elderly patients.

Combination with diagnostic studies: preservatives, which are contained in medicinal forms for ophthalmic use, can suppress the growth of Staphylococcus albus, Pseudomonas, Candida albicans and make it difficult to isolate them in a bacteriological study, therefore it is necessary to cancel such preparations the day before the study.

Instructions

Proxymethacaine (Proxymetacainum)