Dimedrol-darnitsa

INSTRUCTIONS FOR MEDICAL USE OF THE MEDICINAL PRODUCT DIMEDROL-DARNITSA (DIMEDROL-DARNITSA)

Composition:

Active substance: diphenhydramine;

One tablet contains 50 mg of diphenhydramine hydrochloride;

Excipients: potato starch, lactose monohydrate, stearic acid.

Pharmaceutical form. Tablets.

Main physicochemical properties: white, flat cylindrical tablets with bevel and score line.

Pharmacotherapeutic group. Antihistamines for systemic use. Aminoalkyl ether derivatives. Diphenhydramine. ATC code R06AA02.

Pharmacological properties.

Pharmacodynamics.

An antihistamine agent. Blocks H1-histamine receptors, thereby eliminating the effects of histamine: reduces or prevents spasms of smooth muscle in blood vessels, intestine, bronchi and bronchioles, increased capillary permeability, tissue edema, itching and hyperemia. The antihistaminic effect of dimethyldiphenylamine (diphenhydramine) is more pronounced on local vascular reactions in inflammation and allergy than on systemic reactions (reduction in arterial pressure). Exhibits local anesthetic action (when administered orally causes transient numbness of oral mucosa), possesses spasmolytic, ganglion-blocking and central anticholinergic activity. Produces sedative, hypnotic (more pronounced with repeated administration) and moderately expressed antiemetic effects. Effects on the central nervous system are due to blockade of brain H3-histamine receptors and inhibition of central cholinergic structures. More effective against bronchospasm induced by histamine liberators (tubocurarine, morphine, sombrevin), and less active against allergic bronchospasm.

Pharmacokinetics.

Rapidly and well absorbed from the gastrointestinal tract after oral administration. Plasma protein binding is 98–99%. Maximum plasma concentration is reached within 1–4 hours after oral administration. The majority of the administered dose is metabolized primarily in the liver to form diphenylmethoxyacetic acid; a smaller portion is excreted unchanged by the kidneys. Widely distributed throughout the body, crosses the blood-brain barrier and enters breast milk, potentially causing a sedative effect in nursing infants.

The elimination half-life ranges from 2 to 8 hours. Excreted primarily unchanged by the kidneys within 24–48 hours. The effect of the drug develops within 15–30 minutes after oral administration, with maximum effect observed within 1–3 hours. Duration of action is 4 to 6 hours.

Clinical characteristics.

Indications.

For the treatment of allergic reactions: urticaria, hay fever (pollinosis), angioneurotic edema, serum sickness, contact dermatitis, erythema multiforme, eczema, pruritus, hemorrhagic vasculitis (capillarotoxicosis), vasomotor rhinitis, respiratory allergy, acute iridocyclitis.

Allergic eye diseases (conjunctivitis).

For the prevention and treatment of allergic complications, and to reduce side effects associated with the use of medicinal products (antibiotics, enzymes), during blood or blood substitute transfusions.

Chorea, motion sickness (sea and air sickness), Meniere's disease.

As a sedative and hypnotic agent in neurosis, neurasthenia, and insomnia.

Contraindications.

Hypersensitivity to the components of the drug or to other antihistamines; bronchial asthma attack, pheochromocytoma, epilepsy, prolonged QT interval syndrome, or ongoing use of drugs that may prolong the QT interval and/or cause torsade de pointes. Porphyria. Closed-angle glaucoma, benign prostatic hyperplasia, stenosing peptic ulcer of the stomach or duodenum, pyloroduodenal obstruction, bladder neck obstruction, bradycardia, cardiac arrhythmias, history of sudden cardiac death in the family, significant electrolyte imbalance (hypokalemia, hypomagnesemia).

Interaction with other medicinal products and other forms of interaction.

Diphenhydramine enhances the effects of ethanol and agents that depress the central nervous system: neuroleptics, tranquilizers, hypnotics, analgesics, narcotic drugs.

Monoamine oxidase inhibitors (MAO inhibitors) enhance the anticholinergic activity of diphenhydramine. Concurrent use of MAO inhibitors and diphenhydramine may lead to increased blood pressure, as well as affect the central nervous and respiratory systems. The drug should be used with caution during MAO inhibitor therapy or within 2 weeks after discontinuation of MAO inhibitors.

Concomitant use with medicinal products that prolong the QT interval on electrocardiography (ECG), such as class Ia and III antiarrhythmics, should be avoided.

Since diphenhydramine exerts certain antimuscarinic effects, the action of some anticholinergic drugs (e.g., atropine, tricyclic antidepressants) may be enhanced. Therefore, medical advice should be sought before taking diphenhydramine with such medicinal products.

An antagonistic interaction occurs when co-administered with psychostimulants.

Reduces the effectiveness of apomorphine as an emetic agent in poisoning treatment. Enhances anticholinergic effects of medicinal products with m-cholinoblocking activity.

It is not recommended to administer together with medicinal products containing diphenhydramine, including those intended for topical use.

When used concomitantly with * analeptics*, the risk of seizure development increases.

Concurrent use of diphenhydramine with tricyclic antidepressants may enhance its m-cholinoblocking effect, potentially leading to increased intraocular pressure in glaucoma.

Use of diphenhydramine together with antihypertensive medicinal products may intensify feelings of excessive fatigue.

Diphenhydramine is an inhibitor of the cytochrome P450 isoenzyme CYP2D6. Therefore, there is a potential for interaction with drugs primarily metabolized by CYP2D6, such as metoprolol and venlafaxine. Diphenhydramine should not be used in patients receiving any of these medicinal products.

Special precautions for use.

Diphenhydramine should be administered with caution to patients with myasthenia gravis or a history of seizures.

Use with caution in patients with hyperthyroidism, chronic obstructive pulmonary diseases, increased intraocular pressure, cardiovascular disorders, and in elderly patients due to a higher likelihood of developing dizziness, sedation, and arterial hypotension. The medication may cause dry eyes and create discomfort during contact lens wear.

Diphenhydramine use has been associated with QT interval prolongation on electrocardiogram. During post-marketing surveillance, cases of QT interval prolongation and torsade de pointes related to overdose have been reported.

If a patient develops signs or symptoms that may be related to cardiac arrhythmia, treatment should be discontinued immediately and medical help should be sought urgently. Patients should be advised to promptly report any cardiac symptoms.

Diphenhydramine should be used for as short a duration as possible. Tolerance and/or dependence may develop with frequent use. Do not take the medication for more than 7 consecutive days without consulting a physician. Consult a doctor if insomnia persists, as insomnia may be a symptom of a serious underlying condition.

Cases of abuse and dependence have been reported with diphenhydramine use among adolescents or young adults for recreational purposes, as well as in patients with psychiatric disorders and/or a history of substance abuse.

Monitor for signs or symptoms suggestive of abuse.

Avoid using other antihistamines, including topical antihistamines, and cough and cold medications.

Use with caution in patients with recent respiratory diseases (including bronchial asthma, bronchitis) and arterial hypotension.

The drug may worsen the course of obstructive lung diseases, severe cardiovascular disorders, ileus, and conditions with biliary tract obstruction. Diphenhydramine may cause CNS depression as well as induce excitation, hallucinations, and seizures, particularly in cases of overdose.

Use with caution in patients with impaired liver or kidney function.

Dosage reduction may be required for patients with moderate to severe hepatic or renal insufficiency.

Alcoholic beverages are contraindicated during treatment with this medication. Avoid exposure to UV radiation. Use of diphenhydramine as an antiemetic may complicate the diagnosis of appendicitis and recognition of symptoms of overdose with other medications.

Patients with rare hereditary problems of galactose intolerance, lactase deficiency, or glucose-galactose malabsorption should not take diphenhydramine.

Use during pregnancy or breastfeeding.

Diphenhydramine is contraindicated during pregnancy due to inadequate data on safety and efficacy.

If use of the medication is necessary, breastfeeding should be discontinued. Use of diphenhydramine during breastfeeding may cause paradoxical stimulation of the central nervous system in infants.

Ability to affect reaction speed when driving or operating machinery.

During treatment, patients should refrain from potentially hazardous activities requiring heightened attention and rapid psychomotor reactions (e.g., driving vehicles or operating machinery).

Dosage and Administration

For adult patients, administer ½–1 tablet (25–50 mg of diphenhydramine hydrochloride) 1–3 times daily.

For prevention of motion sickness, take ½–1 tablet 30–60 minutes before travel. As a sedative and hypnotic agent, take 1 tablet before bedtime.

The maximum single dose for adults is 2 tablets (100 mg of diphenhydramine hydrochloride); the maximum daily dose is 5 tablets (250 mg of diphenhydramine hydrochloride).

For children aged 6–12 years, administer ½ tablet (25 mg of diphenhydramine hydrochloride) per dose.

The duration of treatment is determined individually by a physician depending on the nature of the disease.

Children

The medicinal product should be used in children aged 6 years and older.

Overdose

Symptoms: dry mouth, dyspnea, mydriasis, facial flushing, central nervous system depression or excitation, tachycardia, arrhythmia, depression of cardiovascular function and respiration, depression, hyperkinesia, confusion, delirium, fever, tremor, dystonic reactions, and ECG changes; in children – development of seizures. High doses of dimenhydrinate may cause rhabdomyolysis, delirium, toxic psychosis, coma, and cardiovascular collapse.

Treatment: induce vomiting, gastric lavage, administration of activated charcoal; symptomatic and supportive therapy with careful monitoring of respiration and arterial blood pressure. Intravenous infusion of plasma substitutes, oxygen therapy. Epinephrine and analeptics must not be used.

Physostigmine may be administered as an antidote in cases of dimenhydrinate overdose at a dose of 0.02–0.06 mg/kg body weight intravenously, repeated several times if anticholinergic symptoms worsen. In cases of physostigmine overdose, administer atropine.

Seizures and pronounced central nervous system stimulation should be treated with parenteral diazepam.

Adverse reactions

Adverse reactions are listed by system organ class and frequency: very common (≥ 1/10), common (≥ 1/100 to < 1/10), uncommon (≥ 1/1,000 to < 1/100), rare (≥ 1/10,000 to < 1/1,000), very rare (< 1/10,000), frequency not known (cannot be estimated from the available data).

Eye disorders: frequency not known – dry eyes, pupil dilation, diplopia, visual disturbances; very rare – increased intraocular pressure.

Ear and labyrinth disorders: frequency not known – acute labyrinthitis, tinnitus, movement coordination disorders.

Respiratory, thoracic and mediastinal disorders: frequency not known – dryness of nasal and pharyngeal mucosa, nasal congestion, bronchial secretion thickening, chest tightness, dyspnea, breathing difficulty.

Gastrointestinal disorders: common – dry mouth; frequency not known – numbness of oral mucosa, anorexia, nausea, epigastric pain, vomiting, diarrhea, constipation.

Renal and urinary disorders: frequency not known – frequent and/or difficult urination, urinary retention.

Nervous system disorders: common – sedation, weakness, somnolence, reduced attention, decreased psychomotor reaction speed, dizziness, fatigue; frequency not known – anxiety, depression, increased excitability (especially in children), insomnia, nervousness, irritability, euphoria, confusion, tremor, neuritis, paresthesia, dyskinesias, headache; very rare – seizures. In patients with focal brain lesions or epilepsy, seizure discharges on electroencephalography (EEG) may be triggered (even with low doses of dimenhydrinate); the medicinal product may provoke an epileptic seizure. Elderly patients are more prone to confusion and paradoxical excitation (e.g. increased energy, restlessness, nervousness).

Cardiac disorders: frequency not known – palpitations, tachycardia, arrhythmia, extrasystoles.

Vascular disorders: frequency not known – arterial hypotension, cyanosis of skin and mucous membranes.

Blood and lymphatic system disorders: rare – thrombocytopenia; frequency not known – agranulocytosis, hemolytic anemia, hemolytic jaundice.

Immune system disorders: frequency not known – hypersensitivity reactions, including anaphylactic shock and angioneurotic edema.

Skin and subcutaneous tissue disorders: frequency not known – hyperemia, skin rashes, pruritus, urticaria; very rare – contact dermatitis.

Musculoskeletal and connective tissue disorders: frequency not known – muscle twitching.

Reproductive system and breast disorders: frequency not known – increased frequency of menstruation, early menstruation.

General disorders and administration site conditions: frequency not known – sweating, chills, photosensitization, fever, hyperthermic syndrome.

Reporting suspected adverse reactions

Reporting of suspected adverse reactions after marketing authorization is an important procedure. It allows continuous monitoring of the benefit-risk balance of the medicinal product. Healthcare professionals are required to report any suspected adverse reactions through the national reporting system.

Shelf life: 4 years.

Storage conditions

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

Keep out of the reach and sight of children.

Packaging

10 tablets in a blister pack; 1 blister pack in a carton; 10 tablets in blister packs.

Prescription status: Prescription only.

Manufacturer: JSC "Pharmaceutical Company "Darnytsia".

Manufacturer's address

Date of last review: