Omnitus^® (Tablets, Drops, Syrup) Instructions for Use

ATC Code

R05DB13 (Butamirate)

Active Substance

Butamirate (Rec.INN registered by WHO)

Clinical-Pharmacological Group

Antitussive drug

Pharmacotherapeutic Group

Central antitussive agent

Pharmacological Action

Butamirate, the active substance of the drug Omnitus^®, is a centrally acting antitussive agent. It is not related to opium alkaloids either chemically or pharmacologically. It does not cause dependence or addiction.

It suppresses cough by having a direct influence on the cough center. It has a bronchodilatory effect (dilates the bronchi). It facilitates breathing by improving spirometry parameters (reduces airway resistance) and blood oxygenation (saturates the blood with oxygen).

Pharmacokinetics

Absorption

Butamirate is rapidly and completely absorbed after oral administration and hydrolyzes into 2-phenylbutyric acid and diethylaminoethoxyethanol. The effect of simultaneous food intake on the processes has not been studied. The plasma levels of 2-phenylbutyric acid and diethylaminoethoxyethanol are fully proportional in the dose range of 22.5-90 mg.

Measurable concentrations of butamirate are detected in the blood 5-10 minutes after administration of doses of 22.5 mg, 45 mg, 67.5 mg, and 90 mg. C_max in plasma is reached 1 hour after administration of all 4 doses, and the mean C_max in plasma is 16.1 ng/ml after a dose of 90 mg.

The mean C_max of 2-phenylbutyric acid is reached within 1.5 hours, and the maximum exposure is observed after administration of 90 mg (3052 ng/ml).

The mean C_max of diethylaminoethoxyethanol is reached at 0.67 hours, and the maximum exposure is also observed after administration of 90 mg (160 ng/ml).

Distribution

Butamirate has a V_d between 81 and 112 l (considering body weight in kg), as well as a high degree of binding to plasma proteins. 2-phenylbutyric acid has a high degree of binding to plasma proteins in the dose range of 22.5-90 mg, with a mean value of 89.3-91.6%. Diethylaminoethoxyethanol is bound to plasma proteins to some extent, with mean values ranging from 28.8 to 45.7%.

There are no data on the penetration of butamirate through the placental barrier and its excretion in breast milk.

Metabolism

Hydrolysis of butamirate occurs rapidly, and metabolite concentrations are detected within 5 minutes. Based on research data, it is believed that these metabolites also have antitussive activity, but there are no clinical data on the metabolism of diethylaminoethoxyethanol. 2-phenylbutyric acid undergoes further partial metabolism by hydroxylation in the para-position.

Excretion

Within 24 hours after drug administration, the main metabolites (77%) consist of conjugated 2-phenylbutyric acid and parahydroxy-2-phenylbutyric acid.

Excretion of 2-phenylbutyric acid, diethylaminoethoxyethanol, and p-hydroxy-2-phenylbutyric acid occurs mainly in the urine.

The concentration of the 2-phenylbutyric acid conjugate in urine significantly exceeds its concentration in plasma. Butamirate is detected in the urine within 48 hours after oral administration of the drug. The amount of butamirate excreted in the urine within 96 hours corresponds to 0.02%, 0.02%, 0.03%, and 0.03% for drug doses of 22.5 mg, 45 mg, 67.5 mg, and 90 mg. Butamirate metabolites are excreted in larger quantities. T_1/2 of butamirate is 1.48-1.93 hours, of 2-phenylacetic acid is 23.26-24.42 hours, of diethylaminoethoxyethanol is 2.72-2.90 hours.

Special patient groups

There are no data on changes in the pharmacokinetics of the drug in patients with impaired liver or kidney function.

Indications

For adults and children aged 3 years and older

• Symptomatic treatment of dry cough of various etiologies.

ICD codes

Dosage Regimen

Tablets

The drug is administered orally before meals.

Tablets are taken before meals, without chewing.

Tablets 20 mg

Adults are prescribed 2 tablets 2-3 times/day; children over 12 years old – 1 tablet 3 times/day; children aged 6 to 12 years – 1 tablet 2 times/day.

Tablets 50 mg

Adults are prescribed 1 tablet every 8-12 hours.

If the cough persists for more than 5 days after starting treatment, a doctor should be consulted.

Syrup

Orally, before meals.

The syrup comes with 1 measuring spoon (volume 5 ml).

Children

• from 3 to 6 years (15-22 kg) – 2 measuring spoons (10 ml) 3 times/day;
• from 6 to 9 years (22-30 kg) – 3 measuring spoons (15 ml) 3 times/day;
• over 9 years (40 kg) – 3 measuring spoons (15 ml) 4 times/day.

The drug is contraindicated in children under 3 years of age.

Adults

6 measuring spoons (30 ml) 3 times/day.

The recommended dose should not be exceeded.

The maximum duration of use of the drug without consulting a doctor is no more than 5 days. If symptoms worsen or there is no improvement after 5 days of treatment, as well as if fever, rash, or persistent headache occurs, a doctor should be consulted for examination and selection of treatment tactics.

Instructions for opening the bottle

The bottle is closed with a cap with a safety device that prevents it from being opened by children. To open the bottle, press down firmly on the cap and turn it counterclockwise. After use, the bottle must be tightly closed; to do this, the bottle cap must be screwed on tightly again.

Drops

Orally, before meals.

Children from 2 months to 1 year 10 drops 4 times/day; from 1 year to 3 years 15 drops 4 times/day; from 3 years and older 25 drops 4 times a day.

If the cough persists for more than 7 days, a doctor should be consulted.

Before using the drug in children under 2 years of age, a doctor should be consulted.

Adverse Reactions

Classification of the frequency of adverse reactions: very common (≥1/10), common (≥1/100, <1/10), uncommon (≥1/1000, <1/100), rare (≥1/10 000, <1/1000), very rare (<1/10 000), frequency unknown (cannot be estimated from the available data).

Nervous system disorders rare – dizziness, drowsiness.

Gastrointestinal disorders rare – nausea, diarrhea.

Skin and subcutaneous tissue disorders rare – skin rash, itching, urticaria.

Contraindications

• Hypersensitivity to butamirate or to any of the excipients;
• Pregnancy;
• Breastfeeding period;
• Concomitant use with expectorant drugs;
• Children under 3 years of age;
• Rare hereditary fructose intolerance (the drug contains sorbitol).

With caution

Due to the presence of ethanol in the composition of Omnitus^® syrup, the drug should be used with caution in patients prone to drug dependence, patients with liver diseases, brain diseases, patients suffering from epilepsy, alcoholism, and children.

Use in Pregnancy and Lactation

Pregnancy

There are no data on the safety of the drug during pregnancy and its passage through the placental barrier. The use of the drug during pregnancy is contraindicated.

Breastfeeding period

It is unknown whether the active substance of the drug or its metabolites pass into breast milk, therefore the use of the drug during breastfeeding is contraindicated.

Pediatric Use

Contraindicated for use in children under 3 years of age.

Special Precautions

The syrup contains sorbitol and saccharin as sweeteners, so the drug in the form of syrup can be used in patients with diabetes mellitus.

The drug contains sorbitol. Patients with rare hereditary fructose intolerance should not take this drug. Sorbitol may have a mild laxative effect; sorbitol contains 2.6 kcal/g.

Glycerol may cause headache, stomach upset, and diarrhea.

The drug contains less than 1 mmol (23 mg) of sodium per dose, i.e., it is practically "sodium-free".

Effect on ability to drive vehicles and operate machinery

Omnitus^® may cause dizziness and drowsiness, therefore, during the treatment period, caution should be exercised when driving vehicles and performing other potentially hazardous activities that require increased concentration and speed of psychomotor reactions.

Overdose

Symptoms: dizziness, drowsiness, nausea, vomiting, diarrhea, impaired coordination of movements, decreased blood pressure.

Treatment gastric lavage; activated charcoal, symptomatic therapy (as indicated).

Drug Interactions

No drug interactions of butamirate have been described.

During treatment with the drug, it is not recommended to consume alcoholic beverages, as well as drugs that depress the central nervous system (including hypnotics, neuroleptics, tranquilizers).

Since Butamirate suppresses the cough reflex, the simultaneous use of expectorants should be avoided to prevent the accumulation of sputum in the airways with the risk of bronchospasm and respiratory tract infection.

Storage Conditions

The drug should be stored out of the reach of children at a temperature not exceeding 25°C (77°F) in the original packaging.

Shelf Life

The shelf life is 4 years. Do not use after the expiration date printed on the package.

The bottle after opening should be stored in the original packaging at a temperature from 15°C (59°F) to 25°C (77°F) and used until the expiration date.

Dispensing Status

The drug is available without a prescription.

Important Safety Information

This information is for educational purposes only and does not replace professional medical advice. Always consult your doctor before use. Dosage and side effects may vary. Use only as prescribed.