Telfast

Telfast is a drug against allergic reactions, a derivative of Terfenadine, which is devoid of cardiotoxic action.

Indications of the telfast

Pathological processes in the body for the use of Telfast:

1. Allergic rhinitis. It happens, both seasonal (in a specific time period), and year-round (a whole year). Characterized by congestion and edema of the nasal passages, the allocation of a considerable amount of colorless mucus.

2. Seasonal fever. It is formed by contact with the pollen of any plant to which there is an increased sensitivity. It appears seasonally, during flowering of the plant and stops on its own, but nevertheless gives the patient unpleasant sensations.

3. Hives. Allergens, which cause this allergic reaction very much, from drugs to food. There is development of an edema around the blood vessels, which expand. Because of this, the patient has red spots on different parts of the skin. They quickly go into a state of bubbles, and the patient begins to experience a seizure.

Release form

The medication is available in the form of tablets coated with a coating in three different doses:

• 30 mg, ten tablets each;
• 120 mg, ten or twenty tablets;
• 180 mg, ten or twenty tablets. 

Pharmacodynamics

The active substance of the drug, Fexophehedin, is a derivative of Terfenadine, exhibits antihistamine, selective antagonistic activity to H1 receptors, without affecting H2 and H3 receptors.

In addition, unlike most medicines for allergies, the medication does not have a calming or any other effect on the central nervous system.

When carrying out tests to assess the allergic reaction to the skin, it was found that the effect of taking Telfast 1 or 2 times a day begins to show efficacy after an hour. And reaches a maximum, preserving its effect throughout the day, for six hours.

Sensitivity to the medication does not develop even after twenty-eight days after the beginning of the use. With the increase in dosage from 10 mg to 130 mg, a dose-dependent growth of the antiallergic effect is observed if Tfas is taken once. For stable efficacy throughout the day, a dose of at least 130 mg was needed if the same model of antiallergic action was used. The reaction to the skin was suppressed by more than eighty percent.

Patients with a seasonal allergic rhinitis who received up to 240 mg of Telfast (twice a day) for fourteen days, while monitoring with the placebo group, showed the same duration of the QTc interval.

The same data is also provided after taking the medicine by healthy people twice a day for 60 mg - six months, 400 mg - 6.5 days, 240 (per day) throughout the year.

If we exceed the concentration of the drug in plasma by 32 times, Telfast will not affect the potassium passages of delayed rectification in the cardiac muscle.

[1]

Pharmacokinetics

Telfast is rapidly absorbed and reaches its maximum density (one to three hours). The concentration at different doses will be different. For example, when used in knocking, 120 mg is 289 ng / ml, 180 mg is 494 ng / ml.

The active substance binds to serum proteins at sixty to seventy percent. Metabolism occurs in the liver or outside it, this is confirmed by the presence of Fexofenadia in urine and feces.

The final half-life is about eleven to fifteen hours, if you take the medication course.

Based on the information of the information that is available at the moment, basically Telfast is excreted in the bile, and a small amount (about ten percent) with urine. 

[2], [3], [4], [5]

Dosing and administration

Children under six years of age are not eligible for medication.

In childhood from six to eleven years - recommended the use of Telfast 30 mg twice a day.

Adults and children from the age of twelve can take Telfast in a dose of 120 or 180 mg once a day.

You need to drink a large amount of water. Its reception is not dependent on eating. If you need a long-term use of a medicine, it is advisable to stick to a length of time in knocking.

Patients who belong to the elderly population or who are deficient in liver or kidney function do not need to change their recommendations for admission.

[7], [8]

Use of the telfast during pregnancy

Telfast can not be used in the gestational period. This is due to the lack of reliable information on the safety of the use of this medication in this period. It should be noted that in studies on animals, there was no adverse effect on the development of the child in utero and post-breeding period, as well as on the course of pregnancy and labor.

Lactation

It is not recommended to use Telfast during breastfeeding, since there is no information on its presence in the mother's milk. But it is worth bearing in mind that Terfenadine has the ability to penetrate into breast milk. This is important because Fexofenadine is a metabolite of Terfenadine. 

Contraindications

For some pathologies, Telfast should be used with caution:

1. Chronic failure of renal function. The process of drug allocation may be disturbed, due to which the duration of its action will increase.
2. Chronic liver failure. Due to a decrease in hepatocyte function, the usual dose of the drug will have a more pronounced and prolonged effect.
3. Mature category of patients. The dose of medication that is needed to achieve the desired effect is needed below the usual, because with age all the body's functions are weakened.
4. Patients with pathology of the heart muscle. You can not consume Telfast to people who suffer from coronary artery disease, or have recently had a heart attack. This is because the medication can significantly increase the load on the heart muscle.

Telfast can not be used in treatment with:

1. With individual sensitivity to any constituent of the drug. In this case, you should consult a doctor to recommend a drug from another anti-allergic group.
2. Breastfeeding period. Since there is a possibility that Telfast can get into the mother's milk and cause the child to develop an increased sensitivity to this medication. This is due to the unstable immune system of infants.

[6]

Side effects of the telfast

Strong adverse effects were not observed. Dyspeptic disorders, headache, weakness and increased drowsiness did not differ in the frequency of occurrence from the indications in the control group.

Overdose

These studies in people without pathologies suggest that when 800 mg of Telfast is used once (or 690 mg twice a day for two months, or 290 mg twice a day for a year), it does not have significant undesirable effects on the body.

But if one-time take six to ten tablets, there may be signs of an overdose. For example, such as: drowsiness, decreased reaction, inhibition. This is because Telfast, due to its very high density in the blood, is likely to have an effect on H3-histamine receptors in the brain.

As the patient will be diagnosed with an overdose, immediately wash his stomach and give him, to prevent further absorption of Telfast into system mildew, activated charcoal. If these actions do not help the patient and his condition worsens, you should immediately call an ambulance. 

[9], [10]

Interactions with other drugs

Telfast can interact with certain medications, for example, with:

1. Erythromcin or Ketoconazole - there is an increase in the density of Telfast in the blood serum two or three times, but without significantly increasing the QTc interval. There is no particular difference between taking these drugs together or as a motor therapy.

2. Omeprazole - there is no interaction when used together.

3. Medicines, the metabolism of which passes in the liver - does not react.

4. Medicines (antacids) that contain aluminum or magnesium - if taken fifteen minutes before the use of Telfast, this will lead to a decrease in the bioavailability of fexofenadine because of its binding in the gastrointestinal tract.

[11], [12], [13]

Storage conditions

Telfast must be stored in a dry place, which will not be accessible to children at a temperature of 25 ° C. 

[14]

Special instructions

Reviews

1. The patients who took Telfast spoke positively about its high efficiency and speed of action. They note that due to the use of this medication in the allergic rhinitis, nasal breathing is quickly restored. But because of the high price and long-term admission (in some pathologies, the medication can take up to several weeks), the medicine also has negative reviews.
2. Medical workers also dismiss Telfast as an effective, reliable remedy. A positive advantage is also the selective blocking of H-histamine receptors (Telfast blocks only H1, without affecting H2 and H3). This significantly reduces the likelihood of side effects even with prolonged use. But doctors also note the high cost of this medicine, because of what to go through the whole scheme of treatment this medicine can not afford all patients. 

Shelf life

The maximum shelf life of the drug is three years.

[15], [16]