Products
In 2009, a water-soluble varnish containing 8% ciclopirox was approved in many countries for the treatment of nail fungus, which is applied once daily (Ciclopoli). It went on sale in January 2011. In many countries, ciclopirox 8% had already been approved for the treatment of nail fungus for a number of years, in France since 1991, in the USA since 1999, but with the old galenics (water-insoluble varnish without hydroxypropylchitosan). In 2014, another varnish was approved in many countries (Ciclocutane nail varnish).
Structure and properties
Ciclopirox (C12H17NO2, Mr = 207.3) exists as a white to yellowish crystalline powder that is sparingly soluble in water.
Effects
Ciclopirox (ATC D01AE14) is fungicidal against dermatophytes, yeasts, molds, and against spores. It has additional anti-inflammatory and antibacterial properties. Studies have shown that the active ingredient penetrates well into the nail plate even after a single application. After evaporation of the solvent, the local concentration of active ingredient increases, resulting in a concentration gradient. After multiple applications, fungicidal concentrations can be measured in the nail. Ciclopirox remains detectable in the nail for up to 2 weeks after discontinuation. The preparation, which is approved in many countries, contains hydroxypropylchitosan (HPC), a water-soluble, semisynthetic biopolymer that acts as a film former. Unlike comparable preparations (e.g. Penlac in the USA), it forms a water-soluble film on the nail that can be washed off and does not need to be filed off or removed with solvent. It is non-sticky and non-shiny and is said to allow better nail penetration. In clinical trials, ciclopirox has been shown to be more effective than placebo for treating nail fungus. Different figures are available on the cure rate.
Mechanism of action
The mechanism of action differs from other antifungal agents, the majority of which inhibit the synthesis of ergosterol. Among other effects, ciclopirox prevents the uptake of vital cellular components into the fungal cell and complexes metal ions such as iron and aluminum, which are involved in important enzymatic reactions in the fungal cell.
Indications
Mild to moderate fungal diseases of the nails (nail fungus) caused by dermatophytes and/or other ciclopirox-sensitive fungi in which the nail matrix is not affected.
Dosage
According to the package insert. Apply thinly once a day on the affected areas. The varnish dries within 30 seconds and is water soluble. Therefore, unlike other products, it does not need to be filed off. The feet should not be washed for at least 6 hours. Therefore, it is recommended to apply it before going to bed. It usually requires a long treatment period of several months to a year, because nails grow slowly.
Contraindications
The nail polish is contraindicated in hypersensitivity and in children under 6 years of age. Full precautions can be found in the drug label.
Interactions
None known to date.
Adverse effects
Rarely, local reactions such as itching, scaling, burning, eczema, and rashes occur on the surrounding skin. The development of allergic contact dermatitis has been attributed to the excipient cetylstearyl alcohol. Changes in nail structure or color may occur.
