Thiamine chloride (vitamin b1)

INSTRUCTIONS FOR MEDICAL USE OF THE MEDICINAL PRODUCT THIAMINE CHLORIDE (VITAMIN B1) (THIAMINE CHLORIDE (VITAMIN B1))

Composition:

Active substance: thiamine hydrochloride;

1 ml of solution contains thiamine hydrochloride 50 mg;

Excipients: unithiol, water for injections.

Pharmaceutical form. Injection solution.

Main physicochemical properties: clear solution ranging from colorless to yellowish or greenish-yellow.

Pharmacotherapeutic group. Simple vitamin B1 preparations. Thiamine (vitamin B1).

ATC code A11D A01.

Pharmacological properties.

Pharmacodynamics.

Thiamine chloride (vitamin B1) is a synthetic water-soluble vitamin B1 preparation. In the body, through phosphorylation processes, it is converted into cocarboxylase, which serves as a coenzyme for many enzymatic reactions.

The drug restores the deficiency of vitamin B1, which plays an important role in metabolism and neuroreflex regulation, affects the conduction of nerve excitation in synapses, and exhibits ganglion-blocking and curare-like effects.

Pharmacokinetics.

After intramuscular administration, the drug is rapidly absorbed. Phosphorylation occurs in the liver. It accumulates in the liver, heart, brain, kidneys, and spleen. Eliminated via the kidneys and intestines, with approximately 8–10% excreted unchanged.

Clinical characteristics.

Indications.

Hypo- and avitaminosis B1 (including in patients undergoing tube feeding, hemodialysis, or suffering from malabsorption syndrome). As part of complex therapy: neuritis, polyneuritis, radiculitis, neuralgia, peripheral paresis and paralysis, neuropathies (diabetic, alcoholic), encephalopathy (including Wernicke-Korsakoff encephalopathy), neurasthenia, chronic liver disorders, myocardiodystrophy, peptic ulcer of the stomach and duodenum, intestinal atony, endarteritis, dermatoses (eczema, atopic dermatitis, pyoderma, psoriasis, lichen planus) with trophic changes and metabolic disturbances.

Contraindications.

Increased individual sensitivity to the components of the drug, allergic diseases, idiosyncrasy, premenopausal and menopausal period in women.

Interaction with other medicinal products and other types of interactions.

Thiamine may reduce the effect of depolarizing muscle relaxants (succinylcholine), choline derivatives, adrenomimetics, and sympathomimetics. Prolonged treatment with anticonvulsant drugs (phenobarbital, phenytoin, carbamazepine), as well as concomitant use with digoxin, indomethacin, and antacid agents, may lead to thiamine deficiency. Thiocarbamide and 5-fluorouracil inhibit thiamine activity. The use of caffeine, sulfur-containing drugs, and estrogens increases the requirement for thiamine; ethanol slows down the rate of thiamine absorption.

The use of cyanocobalamin, pyridoxine complicates the conversion of thiamine into its phosphorylated biologically active form and enhances its allergenic potential. Simultaneous parenteral administration of thiamine with pyridoxine (vitamin B6) or cyanocobalamin (vitamin B12) is not recommended.

Concomitant use with adrenomimetics and sympathomimetics reduces their therapeutic effect.

Thiamine is unstable in alkaline and neutral solutions – co-administration with carbonates, citrates, barbiturates, Cu2+, iodide, ammonium iron citrate, and thiamine acid is not recommended.

Special precautions.

The drug should be prescribed with caution in patients with increased nervous system excitability and in hyperacidic forms of duodenal ulcer.

The injectable form of the drug should be used in patients with impaired intestinal absorption or following gastrectomy, when oral administration of thiamine is not possible (due to nausea, vomiting, pre- and postoperative periods), as well as in severe disease forms or at the beginning of treatment to achieve a therapeutic effect more rapidly.

Injections may be painful due to the low pH of the solution. In patients with alcoholism, symptoms of adverse drug reactions may be intensified. The drug should not be used as a substitute for a balanced diet – only as part of dietary therapy. In patients with thiamine allergy, it is recommended to exclude rice, buckwheat, meat, and bread (containing coarse flour) from the diet.

High-dose thiamine administration may interfere with spectrophotometric determination of theophylline in blood serum and with the detection of urobilinogen using Ehrlich’s reagent.

Parenteral administration should begin with low doses (not more than 0.5 mL for adults), and higher doses should be administered only if well tolerated.

Prior to parenteral administration of thiamine chloride solution, a skin test for individual sensitivity to the drug is mandatory. Anaphylactic reactions occur more frequently after high-dose intravenous administration.

Thiamine injections should preferably be administered no sooner than 12 hours after pyridoxine injection.

When administered intramuscularly, the drug should be injected deeply into the muscle; when administered intravenously, it should be given slowly.

Daily requirement of vitamin B1: in adult males – 1.2–2.1 mg, in elderly individuals – 1.2–1.4 mg, in females – 1.1–1.5 mg, with an additional 0.4 mg for pregnant women and 0.6 mg for women during breastfeeding; in children, depending on age – 0.3–0.5 mg.

In Wernicke's encephalopathy, thiamine should be administered before glucose infusion.

Thiamine may reduce the effectiveness of depolarizing muscle relaxants, adrenolytic agents, and sympathomimetic drugs.

After injection, monitoring for 30 minutes is required due to the risk of severe allergic reactions.

Use during pregnancy or breastfeeding.

Use during pregnancy or breastfeeding is possible at recommended doses under medical supervision.

Ability to affect reaction speed when driving or operating machinery.

During treatment, caution should be exercised when driving vehicles or operating complex machinery due to the potential for adverse nervous system reactions.

Method of administration and dosage.

Administer intramuscularly (deep into the muscle).

For adults: 25–50 mg (0.5–1 mL of the drug) once daily. Administration should begin with low doses [no more than 25 mg (0.5 mL)]. Higher doses [50 mg (1 mL)] should be administered only if well tolerated. Treatment course: 10–30 injections.

For Wernicke-Korsakoff encephalopathy: 50–100 mg (1–2 mL) twice daily intramuscularly until clinical improvement occurs. The possibility of an allergic reaction to vitamin B1 administration should be considered.

For children aged 8 years and older: 12.5 mg (0.25 mL) once daily. Treatment course: 10–30 injections.

Children.

Children are usually administered a 2.5% solution of thiamine hydrochloride. A 5% solution may be administered to children aged 8 years and older.

Overdose.

Symptoms: possible intensification of adverse drug reactions—hypercoagulation, purine metabolism disturbances.

Treatment: discontinuation of the drug; symptomatic therapy.

Adverse Reactions.

Cardiovascular system: tachycardia, palpitations, collapse.

Nervous system: headache, dizziness, anxiety, paresthesia.

Eye disorders: optic nerve damage.

Respiratory system: dyspnea, shortness of breath.

Gastrointestinal tract: dysphagia, nausea, intestinal hemorrhage.

Immune system: rash, pruritus (including at injection site), dermatitis, hyperemia, urticaria, angioneurotic edema, bronchospastic syndrome with convulsions, anaphylactic shock.

Hepatobiliary system: disturbances in liver enzyme activity.

General disorders: increased sweating, chills, tremor, general weakness, edema, fever.

Other: synaptoplegia phenomenon – the ability of thiamine to form complexes with various mediators may be accompanied by decreased arterial pressure, development of cardiac arrhythmias, impaired contraction of skeletal (including respiratory) muscles, and suppression of the central nervous system; thiamine promotes the development of staphylococcal resistance to antibiotics.

Incompatibility.

The solution of "Thiamine chloride (vitamin B1)" should not be mixed with solutions containing sulfites or nicotinic acid – thiamine degradation occurs; with benzylpenicillin or streptomycin – degradation of antibiotics occurs; with carbonates, citrates, barbiturates, Cu2+, iodides, tannic acid – thiamine is unstable in alkaline and neutral solutions.

Shelf life.

2 years.

Storage conditions.

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

Keep out of reach of children.

Packaging. 1 ml in an ampoule. 10 ampoules per cardboard box with partitions; or 5 ampoules in a single-sided blister pack, 2 blisters per cardboard box.

Prescription status.

Prescription only.

Manufacturer.

Private Joint Stock Company "Lekhym-Kharkiv".

Manufacturer's location and address of business activity.

36 Severin Pototskogo Street, Kharkiv, Kharkiv Region, 61115, Ukraine.

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