Pharmacodynamics
Dexpanthenol is an alcohol derivative of pantothenic acid (a B vitamin), which is an essential component of a normally functioning epithelium (the top cell layer of skin tissue). Enzymatically, it is cleaved to pantothenic acid, which is a component of coenzyme A. This in turn acts as a cofactor in many enzymatic reactions in which acetyl groups are transferred. These processes are important for the formation and regeneration of the skin and mucosa by causing increased fibroblast proliferation and accelerated re-epithelialization (i.e., new formation of skin tissue) during wound healing.
In addition, coenzyme A is involved in the synthesis of acetylcholine. Acetylcholine is the transmitter in the parasympathetic (involuntary) nervous system and as such maintains normal intestinal functions. Dexpanthenol may enhance the action of acetylcholine and acts on the gastrointestinal tract by increasing lower intestinal motility.
Pharmacokinetics
Unlike pantothenic acid, dexpanthenol is better absorbed and transported across membranes. The rate of penetration and absorption is reduced when dexpanthenol is administered as an oil/water formula, which is why the drug is usually presented on an ointment base.
Etwa 70 % einer oralen Dosis Pantothensäure werden unverändert im Urin und etwa 30 % im Stuhl ausgeschieden.
Interactions
There are no known drug-drug interactions when applied to the skin.
For theoretical reasons, manufacturers of medications containing dexpanthenol recommend that it not be taken with or within 12 hours of taking neostigmine or other parasympathomimetics (substances that mimic the actions of the involuntary nervous system).
Obwohl die klinische Bedeutung nicht nachgewiesen wurde, können die pupillenverengenden Wirkungen von Anticholinesterase-Augenpräparaten (z. B. Echothiophat-Iodid, Isoflurophat) Berichten zufolge durch Pantothensäure verstärkt werden.
