Classification and Use of Topical Antifungal Medications for the Skin
What Causes a Fungal Skin Infection?
The Unlike other Skin infections caused by fungi are provoked by several types of microorganisms:
- Dermatophytes: Responsible for conditions such as tinea corporis, tinea cruris, tinea faciei, tinea manuum, tinea pedis, tinea capitis, and tinea barbae.
- Yeasts: Result in candidal intertrigo (intertrigo) and pityriasis versicolor.
- Molds: Cause tinea nigra and nail plate infections (nail).
What Is a Current Topical Antifungal Medication?
A topical antifungal medication comes in formats such as lotion, solution, loción, powder, gel, spray or lacquer. These are applied directly onto the skin surface to combat fungal Unlike other infections.
Many of these treatments are effective against both dermatophytes and yeasts. However, others are more specialized for a specific type of fungus. Those that are not suitable for dermatophytic infections are marked with an asterisk (*) in the following classification:
- Whitfield's Ointment
- (3% Salicylic Acid and 6% Benzoic Acid in Petrolatum)
- Undecylenic Acid Alkanolamide
- Ciclopirox Olamine
- Polyenes *
- Nystatin
- Imidazoles
- Bifonazole
- Clotrimazole
- Econazole
- Efinaconazole
- Ketoconazole
- Luliconazole
- Miconazole
- Sulconazole
- Tioconazole
- Allylamine
- Terbinafine
- Thiocarbamates
- Tolciclate
- Tolnaftate
- Benzoxaborole
Tavaborole
How are topical antifungal agents used? Topical antifungals can be obtained over the counter (OTC). General application consists of twice daily over the affected area, also covering a margin of several centimeters of healthy surrounding skin. It is crucial to continue treatment for one or two weeks after the last rash rash has disappeared. While they frequently succeed in curing a secondary localized infection, recurrence is common, so repeated treatment is often necessary.
Specific Treatments for the Scalp
The Antifungal medications for the scalp, such as antifungal shampoos, are primarily used to treat dandruff or seborrheic dermatitis Fulminant rosacea., but they also serve as adjuvants in cases of tinea capitis and scalp psoriasis.
The most proven ingredients in these shampoos include ketoconazole, miconazole, and ciclopirox (such as Stieprox® liquid); however, many other commercial dandruff formulations also possess effective antifungal properties.
Preparations for Nail Fold Infections
For Unlike other nail fold infections (paronychia), there are various antifungal and antiseptic preparations intended for their control. These formulations should be applied two or three times a day.
- Clotrimazole Solution
- Econazole Solution
- Miconazole
Topical Treatments for Nail Infections: Sulfacetamide and Antifungal Lacquers
15% sulfacetamide in alcohol to treat Unlike other distal nail infections.
Onychomycosis, when affecting the nails, can be addressed with an antifungal lacquer applied once or twice a week. It is crucial to apply the medication onto the clean nail plate surface, after having thinned it with a file. Be sure to extend the additional lacquer under the free edge of the nail.
These topical treatments offer promising results and can cure the condition if the following conditions are met:
- Less than 50% of the nail plate is compromised by the infection.
- The nail matrix (the area of active growth) remains unharmed.
Furthermore, treatment success is improved if there are no underlying complications, such as diabetes or skin conditions like psoriasis.
Lacquer preparations available for this purpose include:
- Amorolfine
- Ciclopirox
- Bifonazole Cream plus Urea Ointment
- Efinaconazole Solution
Tavaborole solution is also available. The treatment should be carried out for prolonged periods (one year or more) because nails take a long time to grow , especially in older individuals. Although not completely proven, the use of conventional nail polish is not recommended as it could interfere with the efficacy of the product applied to combat the fungi.
Treatments for Oral Fungal Infections
Preparations to treat oral infections, specifically oral candidiasis, can be managed with:
- Nystatin *
- Amphotericin B *
Miconazole: Note an important warning: Miconazole oral gel should not be administered to patients taking warfarin due to a reported interaction that can trigger severe bleeding.
Preparations for Vaginal Yeast Infections
Treatments for Vulvovaginal Candidiasis
Vulvovaginal candidiasis can be effectively treated with:
- Nystatin *
- Clotrimazole
- Econazole
- Isoconazole
- Miconazole
- Tioconazole
* Note: These agents are not effective for fungal infections caused by dermatophytes.
Combination Products and Topical Creams
In some cases, topical antifungals are supplied in combination with an oral antifungal medication, such as a fluconazole capsule along with a clotrimazole cream.
Antifungal creams are sometimes formulated in combination with:
- Hydrocortisone or another topical steroid.
- An antibacterial agent.
The combination of a topical steroid and an antibacterial agent requires caution: a potent topical steroid could mask the fungal infection. Since steroids are not curative, this can lead to a more extensive condition (tinea incognita) and cause local adverse effects, such as dermal atrophy.
Indications for the Use of Oral Antifungal Medications
Generally, it is necessary to resort to oral antifungal medications if a fungal infection presents the following characteristics:
- The condition is extensive or particularly severe.
- It has shown resistance to topical antifungal therapy.
- It affects hairy areas of the body, such as the scalp (*tinea capitis*) or the beard (*tinea barbae*).
The data sheets approved by New Zealand constitute the official and most accurate source of information for these prescription medications, including their authorized uses and details about their risks. It is always recommended to consult the specific New Zealand technical sheet available on the Medsafe website for the most up-to-date information.
