With oral administration of the drug, its absorption in the gastrointestinal tract is low, which allows maintaining an effective concentration in the lumen of the intestine.
The maximum concentration in the plasma after taking the capsules is observed after 3-4 hours. Half-life is about 10 hours. The maximum excretion is determined after 12-24 hours. The entire preparation is withdrawn after 48 hours.
In healthy volunteers, as well as in patients, tilichinol and tilbroquinol are rapidly absorbed, conjugated in the liver (1st path of metabolism) before entering the systemic circulation.
Both substances are rapidly excreted in the urine: about 40% and 80% of the dose for tilichinol and tilbroquinol, respectively, mostly (99%) in a combined form.
Pharmacokinetic parameters do not depend on the frequency of administration. Cumulation of tilichinol and tilbroquinol is low (cumulation coefficient less than 1.5). In a state of equilibrium, the parameters of excretion of tilichinol are close in value in healthy volunteers and in patients: the half-life is 3.3 h ± 1.9 and 3.1 h ± 1.8, respectively.
The difference between tilichinol and tilbroquinol is as follows:
- after repeated application in serum samples in an unchanged form only tilbroquinol is found;
- Tilichinol (free or in conjugated form) is excreted in the urine in a much larger amount and faster than tilbroquinol.
All this suggests that tilbroquinol in free and in conjugated forms is more active in the body than tilichinol.