Fluimukan

Pharmacotherapeutic group: Mycolytics, ATC code: R05CB01

N-acetyl-L-cysteine (NAC), the active ingredient in Fluimukan 200 mg Powder for Oral Solution exerts an intense mucolytic-fluidizing action on mucous and mucopurulent secretions by depolymerizing the mucoproteic complexes and the nucleic acids which confer viscosity to the vitreous and purulent component of the sputum and other secretions.

Furthermore, Fluimukan exerts a direct antioxidant action, having a free thiol (- SH) nucleophilic group that is able to interact directly with electrophilic groups of oxidant radicals. Of particular interest is the recent finding that Fluimukan protects α1-antitrypsin enzyme inhibiting elastase from inactivation by hypochlorous acid (HOCl), a powerful oxidant agent produced by the myeloperoxidase enzyme of activated phagocytes. Due to its molecular structure, Fluimukan can readily cross cell membranes. Inside the cell, NAC is deacetylated to L-cysteine, an amino acid essential for glutathione synthesis (GSH).

GSH is a highly reactive tripeptide found ubiquitously in the various tissues of animals and is essential for the maintenance of functional capacity as well as cellular morphological integrity. It is the most important protective intracellular mechanism against oxidant radicals, both exogenous and endogenous, as well as toward numerous cytotoxic substances.

These features make Fluimukan 200 mg Powder for Oral Solution particularly suitable for the treatment of acute and chronic affections of the respiratory system, characterised by thick, viscous mucous and mucopurulent secretions.

There is no evidence on the efficacy and safety of mucolytic s including Fluimukan in acute bronchitis.

Absorption

Following oral administration, Fluimukan is rapidly and almost completely absorbed and metabolised in the liver to cysteine (the pharmacologically active metabolite), diFluimukan, cysteine and further mixed disulphides.

Distribution

Due to the high first-pass effect, the bioavailability of orally administered Fluimukan is very low (approximately 10%). In humans, maximum plasma concentrations are achieved after 1-3 hours with the maximum plasma concentration of the metabolite cysteine in the range of approximately 2µmol/l. The protein binding of Fluimukan was determined to be about 50%.

Biotransformation

Fluimukan and its metabolites occur in three different forms in the organism: partially in free form, partially bound to proteins via labile disulphide bonds and partially as incorporated amino acid. Fluimukan is excreted almost exclusively in the form of inactive metabolites (inorganic sulphates, diFluimukan) via the kidneys. The plasma half-life of Fluimukan is approximately 1 hour and is mainly determined by the rapid hepatic biotransformation. Impaired hepatic function therefore leads to prolonged plasma half-lives of up to 8 hours.

Elimination

Pharmacokinetic studies with intravenous administration of Fluimukan revealed a distribution volume of 0.47 1/kg (in total) or 0.59 I/kg (reduced Fluimukan); the plasma clearance was determined to be 0.11 l/h/kg (in total) and 0.84 l/h/kg (reduced Fluimukan), respectively. The elimination half-life after intravenous administration is 30-40 minutes while excretion follows three-phase kinetics (alpha, beta and terminal gamma phase).

Fluimukan crosses the placenta and is detected in cord blood. No information is available regarding excretion in breast milk.

No knowledge is available concerning the behaviour of Fluimukan at the blood- brain barrier in humans

In the absence of compatibility studies, this medicinal product must not be mixed with other medicinal products.

No special requirements for disposal. Any unused product should be disposed of in accordance with local requirements.