Alfagan R

The drug Alfagan R is the commercial name for a medicinal product containing the active substance bralidin (brimonidine). It is an alpha-adrenoreceptor agonist and is used in ophthalmology to reduce intraocular pressure in patients with glaucoma or acute glaucoma attack.

The mechanism of action of bralidin is to constrict retinal vessels and reduce the formation of intraocular fluid, which leads to a decrease in intraocular pressure. This drug is usually used in the form of eye drops.

It is important to note that Alfagan R should be used only as prescribed by a physician, as improper use or self-medication may lead to side effects or adverse reactions. Patients should also be careful when driving or performing other activities that require clear vision, as the drug may cause drowsiness or blurred vision.

Indications Alfagana R

The drug "Alfagan R" (brimonidine) is commonly used in ophthalmologic practice to reduce intraocular pressure. The main indications for its use include:

1. Glaucoma: Brimonidine helps reduce intraocular pressure, which can slow the progression of glaucoma and prevent vision impairment. Glaucoma is a condition in which increased pressure inside the eye can damage optic nerve, which can lead to vision loss.
2. Acute glaucoma attack: The drug can be used to rapidly reduce intraocular pressure in case of an acute glaucoma attack, which is characterized by a sudden increase in pressure inside the eye that can lead to serious consequences for vision.

Release form

Eye drops, solution. Usually available in vials with a dropper for ease of use. The concentration of the active ingredient brimonidine tartrate in the solution may vary, but is most commonly 0.1% or 0.15%. The vials may have different volumes, such as 5 ml, 10 ml, or 15 ml, depending on the manufacturer and packaging.

Pharmacodynamics

Alfagan P, containing the active substance brimonidine tartrate, acts as a selective alpha-2-adrenomimetic. The pharmacodynamics of this drug is related to its ability to stimulate alpha-2-adrenoreceptors in the eye, which leads to two main effects that reduce intraocular pressure:

1. Reduces the production of intraocular fluid (moisture): Alfagan P acts on the ciliary body in the eye to reduce the production of aqueous moisture. This reduces the volume of fluid in the anterior chamber of the eye, resulting in lower intraocular pressure.
2. Improvement of uveoscleral outflow of intraocular fluid: Brimonidine also improves the outflow of intraocular fluid through the uveoscleral pathway, further contributing to the reduction of pressure within the eye.

These two mechanisms of action together effectively reduce intraocular pressure, which is extremely important for the treatment and prevention of open-angle glaucoma and other conditions associated with increased ophthalmotonus.

In addition to reducing intraocular pressure, brimonidine has neuroprotective properties. It can protect the retina and optic nerve from damage caused by high intraocular pressure, which is an important aspect in the long-term management of glaucoma.

Pharmacokinetics

Pharmacokinetics of Alfagan P containing the active substance brimonidine tartrate describes the absorption, distribution, metabolism and excretion of the drug after topical application to the eye.

1. Absorption: After topical application to the eye, brimonidine penetrates through the conjunctiva and cornea. A small amount of the substance may be systemically absorbed through the ocular mucosa. The maximum plasma concentration is usually observed within 1-3 hours after application.
2. Distribution: Brimonidine penetrates well into the tissues of the eye, reaching the necessary concentrations to reduce intraocular pressure. Data on the distribution of brimonidine in the human body are limited, but it is known that it can penetrate the blood-brain barrier.
3. Metabolism: Brimonidine is metabolized in the liver. The main metabolites are hydroxylated derivatives, which are then conjugated to glucuronic acid.
4. Excretion: Brimonidine metabolites and a small amount of unchanged substance are excreted mainly by the kidneys with urine. The plasma elimination half-life is 1 to 3 hours, reflecting the relatively rapid removal of the substance from the systemic bloodstream.

Dosing and administration

The method of administration and dosage of Alfagan R may vary depending on individual physician's instructions and the specific needs of the patient. However, there is a general recommended dosing regimen:

Method of Application:

Alfagan R is intended for topical application into the conjunctival sac of the eye. Hands should be washed thoroughly before application. Tilt the head back, pull the lower eyelid down slightly to form a "pocket" between the eyelid and the eye. Put the drops into this "pocket" without touching the surface of the eye or eyelid with the tip of the dropper to avoid contamination of the drops. Close the eye and gently press on the inner corner of the eye (at the root of the nose) for 1-2 minutes to minimize systemic absorption of the drops. Try not to blink or close the eyelids vigorously.

Dosage:

The standard dosage of Alfagan P for adults and children over 2 years of age is one drop in the affected eye(s) three times a day, 8 hours apart.

It is important to follow the recommended intervals between applications to maintain optimal intraocular pressure. If you are using other eye drops, at least 5-10 minutes should elapse between their application and the use of Alfagan R.

Do not exceed the recommended dose without consulting your doctor, as this may increase the risk of side effects. If you miss a dose, apply the drops as soon as possible, but if the time for the next dose is approaching, skip the missed dose and continue using the drug as scheduled. Do not double the dose to make up for the missed dose.

Use Alfagana R during pregnancy

The use of the drug "Alfagan R" during pregnancy may be contraindicated or requires special caution.

Data on the safety of brimonidine during pregnancy are limited, and its use should only be used for strict medical indications and after careful discussion with a physician. The physician should assess the potential risks to the mother and fetus, as well as the possible benefits of the drug, and decide on its use based on the individual circumstances of each case.

Contraindications

The drug Alfagan R has the following contraindications:

1. Hypersensitivity or allergic reaction to brimonidine or any other component of the drug. People with known allergy to brimonidine or similar drugs should avoid its use.
2. Children under 2 years of age. Safety and efficacy of "Alfagan R" in children under 2 years of age have not been established, therefore the drug is not recommended for use in this age group.
3. Patients with dry eye syndrome or acute keratitis. Brimonidine may aggravate dry eye and cause irritation or worsening of eye conditions in the presence of dry eye syndrome or acute keratitis.
4. Patients taking monoamine oxidase inhibitors (MAOIs) or tricyclic antidepressants. The use of brimonidine in combination with these drugs may increase the risk of hypertensive crisis.
5. Pregnant women and women breastfeeding. The safety of brimonidine use during pregnancy or breastfeeding has not been established, therefore its use in this case should be carried out only after strict medical justification and a physician's decision on benefits and risks.

Side effects Alfagana R

Alfagan P contains the active ingredient brimonidine tartrate and can cause a number of side effects, both topical and systemic. It is important to note that not all patients will experience them, but the following side effects have been reported:

Local side effects:

• Eye redness and irritation: one of the most common side effects, may be accompanied by a burning or itching sensation.
• Allergic reactions: eyelids may become swollen, red, or itchy.
• Blurred vision and sensation of a foreign body in the eye: these symptoms are usually temporary and pass after adaptation to the drug.
• Dry eyes: may require the use of moisturizing drops.
• Photophobia (hypersensitivity to light).

Systemic side effects:

• Headache and dizziness: may occur as a result of systemic exposure to brimonidine.
• Fatigue and drowsiness: especially important for people driving motor vehicles or operating potentially dangerous machinery.
• Dry mouth.
• Allergic reactions: skin itching, redness and swelling.
• Low blood pressure (hypotension).
• Tachycardia or bradycardia (fast or slow heartbeat).

In rare cases, more serious side effects such as depression, shortness of breath, or changes in heart rhythm may occur that require immediate medical attention.

If any side effects occur, you should immediately contact an ophthalmologist to adjust the dosage or change the drug.

Overdose

An overdose of Alphagan R may result in increased side effects associated with the drug, such as drowsiness, decreased blood pressure, decreased heart rate, decreased pupils, eye irritation, and dry mouth.

Interactions with other drugs

The drug Alfagan R (brimonidine) may interact with some other medicines. Here are some of them:

1. Blood pressure-lowering drugs (antihypertensive drugs): Use of Alfagan R in combination with other blood pressure-lowering drugs such as beta-blockers, diuretics, or angiotensin-converting enzyme inhibitors (ACEIs) may result in an increased hypotensive effect and lower blood pressure.
2. Drugs for the treatment of depression and anxiety (antidepressants and anxiolytics): Brimonidine may increase the sedative effect of drugs of this class, which may lead to increased drowsiness and fatigue.
3. Monoamine oxidase inhibitors (MAOIs): The use of Alfagan R in combination with MAOIs may increase the hypotensive effect of the drug and increase the risk of hypotensive crisis.
4. Glaucoma medications: Use of Alphagan R in combination with other ocular glaucoma medications may result in increased reduction of intraocular pressure.

Storage conditions

The drug "Alfagan R" should be stored according to the manufacturer's instructions and your doctor's recommendations. Usually the storage conditions for "Alfagan R" eye drops are as follows:

1. Store the drug at room temperature (15 to 30 degrees Celsius).
2. Do not allow the preparation to freeze.
3. Store the drug in a place protected from light, as light may adversely affect the stability of the drug substance.
4. The bottle or vial of drops should be kept tightly closed to prevent contamination or contamination.
5. Contact of the pipette tip or vial with any surface should be avoided to avoid contamination.

It is necessary to observe the specified storage conditions to maintain the effectiveness and safety of the drug "Alfagan R" throughout its shelf life.