Dimetindene-zdorovya

INSTRUCTION FOR MEDICAL USE OF THE MEDICINAL PRODUCT DIMETINDENE-ZDOROV'YA

Composition:

Active substance: dimetindene;

1 tablet contains dimetindene maleate 1 mg;

Excipients: povidone; microcrystalline cellulose; colloidal anhydrous silicon dioxide; lactose; magnesium stearate; coating containing: sucrose; polyethylene glycol 35000; talc; titanium dioxide (E 171); gelatin; yellow wax; povidone; glucose monohydrate.

Pharmaceutical form. Film-coated tablets.

Main physico-chemical properties: film-coated tablets, white or almost white, round-shaped, biconvex.

Pharmacotherapeutic group. Antihistamines for systemic use.

ATC code R06A B03.

Pharmacological Properties.

Pharmacodynamics.

Dimetindene is a competitive inhibitor of histamine that blocks histamine H1-receptors. At low concentrations, it exerts a stimulating effect on histamine methyltransferase, leading to histamine inactivation. It shows high affinity for histamine H1-receptors and acts as a mast cell stabilizer. In addition, the drug acts as a local anesthetic. It does not affect histamine H2-receptors. Furthermore, dimetindene acts as an antagonist of bradykinin, serotonin, and acetylcholine. It exists as a racemic mixture with R-(–)-dimetindene, which has more pronounced H1-antihistaminic activity. Dimetindene significantly reduces capillary hyperpermeability associated with immediate-type hypersensitivity reactions.

In combination with histamine H2-receptor antagonists, dimetindene maleate inhibits almost all types of histamine effects on the circulation.

Studies on skin response related to histamine action have shown that the effect of a single 4 mg dose of dimetindene in the form of drops on skin reactions persists up to 24 hours after administration.

Pharmacokinetics.

Absorption. Systemic bioavailability of dimetindene in the form of drops is approximately 70%. Initial response to the drug is expected within 30 minutes after administration, with maximum response occurring within 5 hours. Maximum plasma concentration of dimetindene is reached within 2 hours after administration of an oral solution or tablet containing 1 mg of the active substance.

Distribution. At concentrations ranging from 0.09 to 2 µg/mL, binding of dimetindene to human plasma proteins is approximately 90%.

Biotransformation. Metabolic reactions include hydroxylation and methoxylation of the compound.

Elimination. The elimination half-life is approximately 6 hours. Dimetindene and its metabolites are excreted via the liver and kidneys.

Clinical characteristics.

Indications.

Symptomatic treatment of:

• histamine-dependent pruritus;
• pruritus in children caused by chickenpox;
• allergic rhinitis in patients aged 6 years and older;
• urticaria.

Contraindications.

Hypersensitivity to dimetindene maleate or to any of the excipients. Children under 3 years of age.

Interaction with other medicinal products and other forms of interaction.

When two or more drugs that suppress central nervous system (CNS) function are taken simultaneously, an enhanced CNS depressant effect may occur. This can lead to adverse and even life-threatening consequences. Such drugs include opioid analgesics, anticonvulsants, antidepressants (tricyclic antidepressants and monoamine oxidase inhibitors), other antihistamines, antiemetics, neuroleptics, anxiolytics, hypnotics, scopolamine, and ethanol.

To reduce CNS depressant effects and avoid possible potentiation, concomitant administration of procarbazine and antihistamines should be performed with caution.

Antihistamines may potentiate the effects of anticholinergic agents.

Tricyclic antidepressants and anticholinergic drugs (e.g., bronchodilators, gastrointestinal spasmolytics, mydriatics, urological anticholinergics) may exhibit additive anticholinergic effects with antihistamines, increasing the risk of glaucoma exacerbation and urinary retention.

In addition, concomitant use of tricyclic antidepressants may trigger an attack in patients at risk of developing glaucoma.

Special precautions for use

Since adverse effects such as restlessness and fatigue are more likely in elderly individuals, caution should be exercised in this population. The use of this medication should be avoided in elderly patients who are confused. Recommended doses and duration of treatment must not be exceeded without prior consultation with a physician (see section "Dosage and administration").

Like other antihistamines, this medicinal product should be used with caution in patients with glaucoma or congenital or acquired bladder neck obstruction (e.g. prostate hyperplasia).

Dimetindene, like all H1- and partially H2-receptor antagonists of histamine, should be used with caution in patients with epilepsy.

Children. In young children, antihistamines may cause excitatory reactions.

Special warnings regarding inactive ingredients. The medicinal product contains glucose, lactose, and sucrose. In patients with diagnosed intolerance to certain sugars, medical advice should be sought before taking this medicine.

Use during pregnancy or breastfeeding.

Pregnancy.

The safety of dimetindene use during human pregnancy has not been established. Dimetindene should be used during pregnancy only after consultation with a physician and careful assessment of the benefit-risk ratio for the mother and the fetus. In animal studies, no teratogenic effects of dimetindene have been observed. There are also no data indicating any direct or indirect harmful effects on pregnancy, embryonic/fetal development, delivery, or postnatal development.

Breastfeeding period.

It should be noted that dimetindene is excreted into breast milk. The use of this medicinal product is not recommended during breastfeeding.

Fertility.

Animal studies have not shown any effect on fertility.

Ability to influence reaction speed when driving or operating machinery.

This medicinal product may impair psychomotor performance (e.g. causing drowsiness, dizziness) when taken as prescribed. Therefore, driving vehicles or operating machinery should be avoided. This is particularly important when the medicine is taken concomitantly with alcohol.

Method of administration and dosage.

Dosing.

Adults and children aged 12 years and older. The recommended daily dose is 3 to 6 mg of dimetindene maleate, divided into 3 doses.

If not otherwise prescribed, adults should take 1–2 tablets 3 times daily.

For patients prone to drowsiness, it is recommended to take 2 tablets at night and 1 tablet in the morning.

Children aged 3 to 11 years. The recommended daily dose is 0.1 mg of dimetindene maleate per 1 kg of body weight. If not otherwise directed by a physician, children aged 3 years and older should take 1 tablet 3 times daily.

Elderly patients (aged 65 years and older). The usual adult dose may be taken.

The medicinal product must not be used for longer than 14 days without consulting a physician.

Children. Not recommended for children under 3 years of age.

Overdose.

Symptoms. Symptoms of overdose with H1-antihistamines include central nervous system (CNS) depression with dizziness (predominantly in adults), CNS stimulation with antimuscarinic effects (particularly in children and elderly individuals), including agitation, ataxia, hallucinations, tremor, seizures, urinary retention, and hyperthermia. The medicinal product may also cause arterial hypotension, coma, and cardiac or respiratory arrest.

Treatment. There are no specific antidotes for antihistamine overdose. Management measures depend on the clinical manifestations and accepted medical guidelines.

Side effects

The main side effect is drowsiness, which may occur especially at the beginning of treatment. Allergic reactions may very rarely occur.

Side effects are classified by organ system and frequency:

Within each group, adverse effects are listed in order of decreasing severity according to frequency.

Reporting of suspected adverse reactions.

Reporting of adverse reactions after marketing authorization of a medicinal product is of great importance. It enables continuous monitoring of the benefit/risk balance of the medicinal product. Medical and pharmaceutical professionals, as well as patients or their legal representatives, should report all suspected adverse reactions and lack of efficacy via the Automated Pharmacovigilance Information System at the following link: https://aisf.dec.gov.ua.

Shelf life. 2 years.

Storage conditions. Store in the original packaging at a temperature not exceeding 25 °C.

Keep out of reach and sight of children.

Packaging. 10 tablets per blister, 1 or 2 blisters per cardboard box.

Availability category. Over-the-counter (without prescription).

Manufacturer. Limited Liability Company "Pharmaceutical Company "Zdorovya".

Manufacturer's address and location of operations.

22 Shevchenka Street, Kharkiv, Kharkiv Oblast, 61013, Ukraine.