Retinol Acetate

Pharmacological properties

Vitamin A has a general strengthening effect, normalizes tissue metabolism: it participates in redox processes (due to the large number of unsaturated bonds), in the synthesis of mucopolysaccharides, proteins, lipids, in mineral metabolism, and the formation of xc. enhances the production of lipase and trypsin, enhances myelopoiesis, cell division processes. has a positive effect on the function of the lacrimal, sebaceous and sweat glands; increases resistance to diseases of the mucous membrane of the respiratory tract and intestines; increases the bodys resistance to infections. enhances the multiplication of skin epithelial cells, rejuvenates the cell population and reduces the number of cells that go through terminal differentiation, inhibits keratinization processes, enhances the synthesis of glycosaminoglycans, activates the interaction of immunocompetent cells with each other and epidermal cells. stimulates skin regeneration. retinol is a necessary component for the normal function of the retina of the eye: it binds to opsin (the red pigment of the retina), forming visual purpura - rhodopsin, which is necessary for visual adaptation in the dark.

Local action is mediated by the presence on the surface of epithelial cells of specific retinol-binding receptors.

Vitamin A is almost completely absorbed in the intestine (mainly in the duodenum and rectum). After taking C_max the drug in the blood plasma is observed after 4 hours. Retinol is distributed unevenly in the body. The greatest amount of it is in the liver and retina, it is determined in the kidneys, fat depots, adrenal glands and other endocrine glands. Retinol metabolites are excreted by the kidneys. T_½ - 9.1 hours. In the urine of a healthy person, retinol is not determined, since it is excreted in the composition of bile.

Indications

Treatment for vitamin deficiency a and hypovitaminosis a.

Eye disease: retinitis pigmentosa, xerophthalmia, hemeralopia, eczema lesions of the eyelids, superficial keratitis, corneal lesions, conjunctivitis, pyoderma.

Disease and skin lesions: frostbite, burns, wounds, ichthyosis, follicular dyskeratosis, senile keratosis, skin tuberculosis, psoriasis, some forms of eczema.

Combined therapy for rickets, collagenosis, malnutrition.

As part of complex therapy for acute respiratory diseases that occur against the background of exudative diathesis, chronic diseases of the respiratory system; inflammatory, erosive and ulcerative lesions of the intestine, cirrhosis of the liver.

Application

Retinol acetate is used for therapeutic purposes for adults with vitamin deficiency moderate and mild severity. prescribe the drug inside 10-15 minutes after eating.

Given the ability of vitamin A to accumulate in the body, before taking the drug, you should pay attention to the dose of retinol palmitate (especially for capsules of 100,000 IU).

The highest daily dose for adults should not exceed 100,000 IU.

For therapeutic purposes, for mild to moderate vitamin deficiency, adults should be prescribed up to 33,000 IU / day, for eye diseases - 33,000–100,000 IU / day. With skin diseases for adults - 33,000-100,000 IU / day.

Doses and duration of treatment with Vitamin A are determined by the doctor individually.

Contraindications

Hypersensitivity to the components of the drug, acute and chronic nephritis, heart failure of degree II – III, gallstone disease, chronic pancreatitis, hypervitaminosis a, overdose of retinoids, hyperlipidemia, obesity, chronic alcoholism, sarcoidosis (including a history).

Side effects

From the digestive tract: loss of appetite, dry mucous membrane of the oral cavity, pain in the stomach, vomiting, nausea.

From the liver and biliary system: hepatotoxic phenomena, portal hypertension.

On the part of the skin and subcutaneous tissue: cracks and dryness of the skin, lips, yellow-orange spots on the soles, palms, nasolabial triangle, subcutaneous edema, in some cases, itchy spotty-papular rashes may occur on the 1st day of use, in in this case, it is necessary to cancel the drug.

From the nervous system: asthenia, excessive fatigue, drowsiness, discomfort, headache, irritability, intraocular hypertension, impaired vision, impaired gait.

From the endocrine system: oligomenorrhea.

From the urinary system: pollakiuria, nocturia, polyuria.

From the blood system: hemolytic anemia.

From the musculoskeletal system: bone pain, changes in the x-ray of the bones, cramps.

Others: hyperthermia, hair loss, photosensitivity, weight loss, hypercalcemia; when using the drug, hypersensitivity reactions are possible.

With a decrease in dose or with temporary discontinuation of the drug, side effects disappear on their own.

In case of skin diseases, the use of the drug in high doses after 7-10 days of treatment may be accompanied by an exacerbation of the local inflammatory reaction, which does not require additional therapy and further decreases. This effect is associated with the myelo and immunostimulating effect of the drug.

special instructions

The drug has the ability to accumulate and for a long time to be in the body, so you should not take the drug with other drugs, which include vitamin a. prolonged daily intake of the drug, especially in high doses due to cumulation in the body, can provoke the development of hypervitaminosis a.

Use the drug with caution in diseases accompanied by blood clotting disorders or those accompanied by loss of calcium in the body, with severe liver damage, acute and chronic hepatitis. To control liver function before and during treatment, a biochemical blood test is required.

It is not recommended to use the drug during prolonged tetracycline therapy.

Retinol should be taken 1 hour or 4-6 hours after taking cholestyramine.

For the normal absorption of vitamin A, the necessary condition is the presence of fats in food.

The abuse of alcohol and tobacco disrupts the absorption of the drug in the digestive tract.

Use during pregnancy and lactation. Given the content of a high dose of vitamin A, the drug is contraindicated during pregnancy and lactation.

Children. The drug is contraindicated in children.

The ability to influence the speed of reactions when driving vehicles or working with other mechanisms. There is no data on the effect of the drug on the ability to drive vehicles or work with complex mechanisms.

Interactions

Estrogens and oral contraceptives that contain them enhance retinol absorption, which can lead to the development of hypervitaminosis a. colestyramine, colestipol, mineral oils, neomycin reduce the absorption of vitamin A (it may be necessary to increase its dose). nitrites interfere with the absorption of retinol.

During prolonged tetracycline therapy, vitamin A is not recommended in high doses (≥50,000 IU) because of the increased risk of developing intracranial hypertension. Retinol weakens the effect of Ca preparations²⁺, increases the risk of hypercalcemia. Isotretinoin increases the risk of toxic effects.

Vitamin E reduces toxicity, absorption, deposition of vitamin A in the liver; high doses of vitamin E can reduce the bodys vitamin A stores. Retinol reduces (mutually) the danger of hypervitaminosis D. GCS and alcohol use reduce the therapeutic effect of the drug.The simultaneous intake of vitamin A and anticoagulants increases the tendency to bleeding. Retinol reduces the anti-inflammatory effect of corticosteroids.

Overdose

Symptoms: severe headache, dizziness; drowsiness, confusion, impaired vision, convulsions, indomitable vomiting, profuse diarrhea, severe dehydration, irritability; on the 2nd day, a common rash appears with further large-peeling peeling, starting from the face; bleeding of the gums, dryness and ulcer of the oral mucosa, peeling of the lips, palpation of long tubular bones is sharply painful due to subperiosteal hemorrhages, pain in the joints and muscles.

Treatment: symptomatic; as an antidote, prescribe thyroxine, as well as ascorbic acid.

Storage conditions

At a temperature not exceeding 25 ° c.