Recent updates in oral terbinafine: its use in onychomycosis and tinea capitis in the US

Now that griseofulvin is not available, what to do with tinea capitis treatments?

INTRODUCTION

Griseofulvin, discovered in 1939 and commercially available since 1959, was the first oral antifungal agent effective against dermatophytosis, particularly tinea capitis. Although it was eventually superseded by azole antifungals due to its long treatment duration and reliance on keratopoiesis, griseofulvin remains notable for its effectiveness and safety in treating tinea capitis, especially when caused by Microsporum canis. However, due to a decline in cases and commercial unavailability, alternative treatments are now required.

AREAS COVERED

The following topics regarding to other treatments were discussed: (I) The efficacy of alternative antifungal agents such as terbinafine, itraconazole, and fluconazole, in the treatment of tinea capitis. (II) The use and role of topical therapies. (III) Experience in the management of tinea capitis.

EXPERT OPINION

The usefulness of oral terbinafine as a replacement for griseofulvin in the treatment of tinea capitis and why it is the preferred drug in elderly patients was discussed. Challenges with Microsporum spp. and the use of fluconazole in pediatric patients were also analyzed. Support for the use of topical treatment as an adjunctive treatment for tinea capitis was highlighted.

Quality assurance of postharvest grapes against Botrytis cinerea by terbinafine

Worldwide, fruit is an indispensable treasure house of nutrition for human beings, occupying a vital position of human diet. Postharvest fruit storage requires efficient antifungal agents to control Botrytis cinerea, which is a vital postharvest disease affecting fruit and leading to enormous losses. However, with the enormous abuse of existing antifungal drugs, the problem of drug-resistant fungi is imminent, making the controlling diseases caused by pathogenic fungi even more challenging. Drug repurposing is an efficient alternative method, we evaluated a well-known antifungal chemical, terbinafine, against the agricultural pathogen, B. cinerea in vitro, as a result, terbinafine showed strong antifungal activity. Furthermore, the in vivo antifungal activity of terbinafine was evaluated, the results showed that terbinafine could reduce the decay area on grapes. Terbinafine could disrupt the cell membrane integrity, increase cell membrane permeability, and eventual cell death of B. cinerea. In addition, terbinafine reduced decay incidence, and weight loss and maintained the soluble solids, titratable acidity, ascorbic acid, total phenolic, and malondialdehyde content during the storage period of grapes. Overall, terbinafine could be an antifungal preservative for postharvest table grapes fresh-keeping.

Advances of liposomal mediated nanocarriers for the treatment of dermatophyte infections

Due to the adverse effects associated with long-term administration of antifungal drugs used for treating dermatophytic lesions like tinea unguium, there is a critical need for novel antifungal therapies that exhibit improved absorption and minimal adverse effects. Nanoformulations offer a promising solution in this regard. Topical formulations may penetrate the upper layers of the skin, such as the stratum corneum, and release an appropriate amount of drugs in therapeutic quantities. Liposomes, particularly nanosized ones, used as topical medication delivery systems for the skin, may have various roles depending on their size, lipid and cholesterol content, ingredient percentage, lamellarity, and surface charge. Liposomes can enhance permeability through the stratum corneum, minimize systemic effects due to their localizing properties, and overcome various challenges in cutaneous drug delivery. Antifungal medications encapsulated in liposomes, including fluconazole, ketoconazole, croconazole, econazole, terbinafine hydrochloride, tolnaftate, and miconazole, have demonstrated improved skin penetration and localization. This review discusses the traditional treatment of dermatophytes and liposomal formulations. Additionally, promising liposomal formulations that may soon be available in the market are introduced. The objective of this review is to provide a comprehensive understanding of dermatophyte infections and the role of liposomes in enhancing treatment.

Clinical Manifestations and Management of Terbinafine-Induced Acute Generalized Exanthematous Pustulosis

Background. Acute generalized exanthematous pustulosis (AGEP) is a rare and serious adverse reaction of terbinafine. Understanding AGEP and terbinafine is primarily based on case reports. The purpose is to explore the clinical characteristics of terbinafine-induced AGEP, and to provide reference for clinical diagnosis and treatment. Methods. Case reports and original studies of terbinafine-induced AGEP were retrieved by searching Chinese and English databases from January, 1991, to May 31, 2022. Results. The median age of the 32 patients (17 males and 15 females) was 55 years (range: 6–84). The median time to onset of AGEP is 8 days (range: 1–77) and is usually accompanied by fever (>38°C) and elevated neutrophil levels (>8000/mm3). Four patients (12.5%) had oral mucosal involvement, and 10 patients (31.3%) developed postpustular desquamation. The lesions were mainly distributed in the trunk (43.8%), the whole body (34.4%), and the extremities (53.1%). Skin biopsy revealed subcorneal pustules (65.6%), intraepidermal cavernous pustules (43.8%), necrotic keratinocytes (15.6%), spongy hyperplasia (25.0%), neutrophil exocytosis (34.4%), and papillary dermal edema (40.6%). AGEP resolved completely in all patients at a median time of 12 days (range: 2–90) after discontinuation of terbinafine and symptomatic therapy. Conclusion. Clinicians should be aware that terbinafine-induced AGEP is a rare cutaneous adverse reaction. AGEP usually occurs within 2 weeks after administration and has a good prognosis after discontinuation.

Determination of terbinafine in human plasma using UPLC-MS/MS: Application to a bioequivalence study in healthy subjects

A high-throughput and sensitive ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method has been developed for the determination of terbinafine in human plasma. The method employed liquid-liquid extraction of terbinafine and terbinafine-d7 (used as internal standard) from 100 μL human plasma with ethyl acetate-n-hexane (80:20, v/v) solvent mixture. Chromatography was performed on a BEH C₁₈ (50 × 2.1 mm, 1.7 μm) column using acetonitrile-8.0 mm ammonium formate, pH 3.5 (85:15, v/v) under isocratic elution. For quantitative analysis, MS/MS ion transitions were monitored at m/z 292.2/141.1 and m/z 299.1/148.2 for terbinafine and terbinafine-d7, respectively, using electrospray ionization in the positive mode. The method was validated according to regulatory guidance for selectivity, sensitivity, linearity, recovery, matrix effect, stability, dilution reliability and ruggedness with acceptable accuracy and precision. The method shows good linearity over the tested concentration range from 1.00 to 2000 ng/mL (r²  ≥ 0.9984). The intra-batch and inter-batch precision (CV) was 1.8-3.2 and 2.1-4.5%, respectively. The method was successfully applied to a bioequivalence study with 250 mg terbinafine in 32 healthy subjects. The major advantage of this method includes higher sensitivity, small plasma volume for processing and a short analysis time.

Novel Drug Delivery Strategies for the Treatment of Onychomycosis

Onychomycosis accounts for 50% of all nail disease cases and is commonly caused by dermatophytes. It was primarily considered a cosmetic problem but has been garnering attention lately due to its persistent nature and difficult treatment with relapses. With prolonged treatment duration and high cost involved in treating onychomycosis, several attempts have been made in overcoming the rigid nail barrier. The conventional treatment of onychomycosis involves oral and topical therapy. The oral antifungal agents though quite effective, are hepato-toxic and cause drug-drug interactions. Topical therapy is more patient compliant being devoid of such adverse effects but it suffers from another setback of improper nail penetration. Amorolfine and ciclopirox nail lacquers are popular market products. Since decades, efforts have been made to enhance topical delivery for efficiently treating onychomycosis. Mechanical, physical and chemical methods have been employed. Despite all the attempts made, the nail delivery issues are far from being solved. Recently, the focus has shifted to novel drug delivery systems like nanoparticles, microemulsions, polymeric films and nail lacquers for enhanced drug permeation and localized therapy. The research around the world is exploring their potential as effective treatment options. This review intends to further explore the novel delivery strategies to treat a persistent fungal infection like onychomycosis.

Kerion Type of Tinea Capitis Treated with Double Pulse Dose Terbinafine

Objective: Tinea capitis is a common dermatophyte infection affecting hair and skin which always requires systemic treatment to get a clinical and mycologic cure, preventing relapse, and infection spread. Griseofulvin has been the antifungal therapy of choice for tinea capitis, but it often requires higher doses and a longer duration than recommended. Thus, effective alternative antifungal with good oral tolerability and shorter course of treatment are therefore required. The objective of this report is to evaluate the effectiveness of double pulse dose terbinafine for tinea capitis alternative therapy.Method: A case of kerion type of tinea capitis in a two-year-old girl was reported. Diagnosis was established based on clinical manifestations of alopecia, presented as erythematous macule with pustules, hemorrhagic crusts, and scales on the scalp, accompanied with occipital lymphadenopathy. Fungal culture showed growth of Microsporum canis (M. canis) colonies. Patient was treated with doubled pulse dose terbinafine 125 mg/day and 2% ketoconazole shampoo for two months.Result: Clinical improvements were found on 35th day of follow up, while mycologic cure was achieved on 60th day of follow up. Tolerability was excellent and no side effects observed.Conclusion: Double pulse dose terbinafine is effective for kerion type of tinea capitis. Key words: double pulse dose, kerion, M. canis, terbinafine, tinea capitis

Aplastic anemia associated with oral terbinafine: a case report and review of the literature

Onychomycosis (OM) is a common fungal infection of the toenails and/or fingernails that is highly prevalent in the general population and also responsible for significant morbidity. OM is caused by dermatophytes, nondermatophytic molds, or yeast. Today systemic antifungal agents are considered as the gold standard for all types of OM. Here we report a case of aplastic anemia associated with oral terbinafine use and a review of the literature on hematological toxicities associated with terbinafine.

Pharmaceutical care of hepatic injury associated with antifungal drugs

Drug-induced liver injury refers to hepatotoxicity or allergic reactions caused by drugs or their metabolites, and it is divided into three categories: liver cell type, cholestasis type and mixed type. Antifungal drugs have many types, including antibiotics, allylamine, azoles, pyrimidine, echinocandins and so on. Most of these drugs are metabolized mainly in the liver, and can cause different degrees of damage to the liver. This article reviews the characteristics of various kinds of antifungal drugs which cause liver damage, and proposes the pharmaceutical case of hepatic injury associated with antifungal drugs. During antifungal therapy liver function should be monitored to evaluate the possibility and severity of hepatic injury. Liver-protecting treatment should be given in time when hepatic injury occurs. Timely reduction or replacement of antifungal drugs is necessary, and the drug should be discontinued when hepatic injury is serious.

DA 5505: a novel topical formulation of terbinafine that enhances skin penetration and retention

Topical fungal infections can become severe if left untreated. Efficient treatment modalities for topical fungal infections aid the penetration of antifungal agents deep into viable skin layers. Terbinafine is a fungicidal agent that inhibits ergosterol, an essential fungal component. The main objective of this study was to evaluate skin permeation and retention of a terbinafine-loaded solution containing chitosan as a film former. Comparative assessment of skin permeation and retention was performed using a prepared formulation (DA 5505) and marketed formulations of terbinafine in murine and porcine skin. To mimic fungal infection of skin, keratinized skin was induced in NC/Nga mice. In comparison with the marketed formulations, DA 5505 exhibited significantly better skin permeation. The flux, permeation coefficient, and enhancement ratio of terbinafine were remarkably increased by DA 5505 in comparison with the marketed formulations, and lag time was dramatically reduced. DA 5505 significantly increased cumulative terbinafine retention in viable skin layers in comparison with the marketed solution, suggesting enhanced efficacy. Furthermore, DA 5505 exhibited superior skin permeation in normal skin and keratinized skin. Thus, the DA 5505 formulation has the potential to effectively deliver terbinafine to superficial and deep cutaneous fungal infections.

Onychomycosis: clinical, mycological and in vitro susceptibility testing of isolates of Trichophyton rubrum

BACKGROUND

Onychomycosis or nail fungal infection is the most common nail disease. Despite the wide range of studies on this condition, it remains difficult to establish the correct diagnosis and effective treatment.

OBJECTIVES

To evaluate the efficacy of classical laboratory methods for the diagnosis of onychomycosis, and the in vitro susceptibility of the its main etiological agent to antifungals used in routine.

METHODS

Nail samples of 100 patients with clinically suspected feet onychomycosis were collected to confirm the diagnosis by direct mycological examination and fungal culture. In vitro antifungal susceptibility testing was performed against strains of the main dermatophyte isolated by microdilution, according to the standardized protocol (M38-A2 - CLSI)

RESULTS

Clinical diagnosis of onychomycosis was confirmed by laboratory analysis in 59% of patients. Of these, 54.2% were positive only in direct mycological examination, 44.1% in direct mycological examination and culture, and one case (1.7%) was positive only in culture, resulting in weak agreement between these tests (Kappa = 0.385; p <0.001) High minimum inhibitory concentration values of fluconazole and itraconazole were observed in 66.7% and 25.0% of isolates of T. rubrum tested. Additionally, high MIC values of terbinafine and ciclopirox was detected in only one isolate, and this was one of the strains in which in vitro activity of itraconazole and fluconazole has not been proven.

CONCLUSIONS

Poor agreement was observed between direct mycological examination and culture for the diagnosis of onychomycosis, with direct mycological examination being significantly more sensitive. Except for fluconazole, the other three antifungals tested showed good in vitro activity against clinical isolates of T. rubrum.

Antifungal therapy for onychomycosis in children

Onychomycosis is a chronic infection of the nail unit, and its prevalence increases with age. Treatment options for children are similar to those for adults and include both oral and topical therapies. Oral agents, such as terbinafine, itraconazole, and fluconazole have been reported to have good efficacy and a low rate of side effects in children. Topical therapies, such as amorolfine and ciclopirox, can also be used as monotherapy or combined with oral agents to treat onychomycosis. Due to their thinner, faster-growing nails, children are more likely to respond to topical monotherapy than adults. There is currently insufficient data comparing emerging medical devices, such as laser therapy, with standard therapeutic options to recommend their use in children.

A metoprolol-terbinafine combination induced bradycardia

To report a sinus bradycardia induced by metoprolol and terbinafine drug-drug interaction and its management. A 63 year-old Caucasian man on metoprolol 200 mg/day for stable coronary artery disease was prescribed a 90-day course of oral terbinafine 250 mg/day for onychomycosis. On the 49th day of terbinafine therapy, he was brought to the emergency room for a decrease of his global health status, confusion and falls. The electrocardiogram revealed a 37 beats/min sinus bradycardia. A score of 7 on the Naranjo adverse drug reaction probability scale indicates a probable relationship between the patient's sinus bradycardia and the drug interaction between metoprolol and terbinafine. The heart rate ameliorated first with a decrease in the dose of metoprolol. It was subsequently changed to bisoprolol and the heart rate remained normal. By inhibiting the cytochrome P450 2D6, terbinafine had decreased metoprolol's clearance, leading in metoprolol accumulation which has resulted in clinically significant sinus bradycardia.

Update on therapy for superficial mycoses: review article part I

Superficial fungal infections of the hair, skin and nails are a major cause of morbidity in the world. Choosing the right treatment is not always simple because of the possibility of drug interactions and side effects. The first part of the article discusses the main treatments for superficial mycoses - keratophytoses, dermatophytosis, candidiasis, with a practical approach to the most commonly-used topical and systemic drugs , referring also to their dosage and duration of use. Promising new, antifungal therapeutic alternatives are also highlighted, as well as available options on the Brazilian and world markets.

Comparison of once-daily versus twice-weekly terbinafine administration for the treatment of canine Malassezia dermatitis - a pilot study

BACKGROUND

Terbinafine, an allylamine antifungal, is used in pulsatile dose regimens for superficial mycoses in human medicine.

OBJECTIVES

To compare the clinical efficacy of twice-weekly versus once-daily terbinafine administration to determine whether preliminary proof-of-concept evidence exists for pulsatile administration of terbinafine in the treatment of canine Malassezia dermatitis and to determine whether twice-weekly treatment results in fewer clinical and owner-perceived adverse events.

ANIMALS

Twenty client-owned dogs with Malassezia dermatitis.

METHODS

In this randomized, single-blinded clinical trial, dogs were randomly assigned to receive terbinafine (30 mg/kg) either once daily for 21 days (n = 10) or once daily on two consecutive days per week for six doses (n = 10). On day 0 and day 21, a mean yeast count was calculated from eight anatomical locations via adhesive tape-strip cytology, clinical lesion scores were assigned to the same locations, and owners assessed pruritus using a visual analog scale.

RESULTS

There was no significant difference between treatment groups with respect to the reduction in mean yeast count (P = 0.343) and clinical lesion scores (P = 0.887). Pruritus measured by visual analog scale was significantly decreased in the twice-weekly treatment group compared with the daily treatment group (P = 0.047). Seven of 20 dogs had a clinically measurable or owner-reported adverse event during treatment that included gastrointestinal disturbances, excessive panting and elevated hepatic enzymes, with no significant difference noted between treatment groups.

CONCLUSIONS AND CLINICAL IMPORTANCE

This pilot study indicates that twice-weekly terbinafine administration may be an effective alternative treatment for canine Malassezia dermatitis and merits further investigation.

New concepts in median nail dystrophy, onychomycosis, and hand, foot, and mouth disease nail pathology

Nails are underutilized as diagnostic tools, despite being involved in many dermatologic conditions. This paper explores new concepts in the treatment of median nail dystrophy (MND), onychomycosis, and the nail pathology of hand, foot, and mouth disease (HFMD). A Pubmed database literature search was conducted for MND treatment, onychomycosis treatment, and HFMD nail pathology. Only papers published after January 2008 were reviewed. The results showed that 0.1% tacrolimus ointment can be an effective treatment for MND. Early studies on laser therapy indicate that it is a safe and efficacious treatment option for onychomycosis, compared to conventional oral antifungal agents. Vicks VapoRub (The Proctor & Gamble Company, Cincinnati, OH) is effective against onychomycosis and is a reasonable option in patients who choose to forgo conventional treatments. Lastly, there is evidence to support a correlation between HFMD and onychomadesis.