The key difference between fluconazole and ketoconazole is that the range of effectiveness of fluconazole is comparatively higher than that of ketoconazole. The range of effectiveness of fluconazole is 74-100%, while the range of effectiveness of ketoconazole is 42-97%.
Fluconazole and ketoconazole are useful antifungal agents that are important in treating fungal diseases on the skin. The trade names for fluconazole and ketoconazole are Diflucan and Nizoral, respectively.
CONTENTS
1. Overview and Key Difference
2. What is Fluconazole
3. What is Ketoconazole
4. Fluconazole vs Ketoconazole in Tabular Form
5. Summary – Fluconazole vs Ketoconazole
What is Fluconazole?
Fluconazole is an antifungal medication for treating fungal infections, including candidiasis, blastomycosis, coccidioidomycosis, cryptococcosis, histoplasmosis, dermatophytosis, and pityriasis versicolor. The chemical formula of fluconazole is C13H12F2N6O, and the molar mass is 306.27 g/mol. The melting point is around 138-140°C.
Figure 01: The Chemical Formula of Fluconazole
Fluconazole falls into the class of azoles, which are antifungals. However, it is different from other azole antifungals by the presence of a triazole ring instead of an imidazole ring (as in other azoles). In addition, fluconazole is for oral use (unlike imidazole antifungals). Fluconazole works best against Candida species, some dimorphic fungi, and dermatophytes.
Common side effects of fluconazole include rashes, headache, dizziness, nausea, diarrhoea, etc. Some rare side effects include oliguria, seizures, alopecia, liver failure, etc. There are very rare adverse effects as well. Ex: prolonged QT interval.
What is Ketoconazole?
Ketoconazole is a medication used to treat a number of fungal infections. It is sold under the brand name Nizoral. We can categorize it as an anti-androgen and antifungal medication. It is applied to the skin to treat fungal skin infections, including tinea, cutaneous candidiasis, pityriasis versicolor, and dandruff.
Figure 02: The Chemical Structure of Resonance Structures of Ketoconazole
The side effects that can be caused by this medication include nausea, headache, and liver problems. When it is applied to the skin, it can also show redness. Moreover, liver problems can result in death or the need for liver transplantation.
The common routes of administration include oral administration as tablets and topical administration as cream, shampoo, or solution. When orally taken, it has a bioavailability of 37 – 97%. Besides, the protein binding ability ranges from 84 – 99%. The metabolism of ketoconazole occurs in the liver, and the elimination is biphasic. The excretion of this medication can occur biliary and through the kidney. The chemical formula of ketoconazole is C26H28Cl2N4O4. The molar mass of this compound is 531.43 g/mol.
What is the Difference Between Fluconazole and Ketoconazole?
Fluconazole and ketoconazole are important in treating fungal diseases on the skin. The key difference between fluconazole and ketoconazole is that the range of effectiveness of fluconazole is comparatively higher than that of ketoconazole. These effectiveness ranges can be given as 74-100% for fluconazole and 42-97% for ketoconazole. Moreover, trade names for fluconazole and ketoconazole are Diflucan and Nizoral, respectively. In addition, ketoconazole is more toxic than fluconazole. While fluconazole is able to penetrate the cerebrospinal fluid, ketoconazole is unable to penetrate the cerebrospinal fluid.
The below infographic presents the differences between fluconazole and ketoconazole in tabular form for side-by-side comparison.
Summary – Fluconazole vs Ketoconazole
Fluconazole and ketoconazole are two antifungal medications for treating fungal infections. The key difference between fluconazole and ketoconazole is that the range of effectiveness of fluconazole is comparatively higher than that of ketoconazole. The range of effectiveness of fluconazole is 74-100%, while the range of effectiveness of ketoconazole is 42-97%.
Reference:
1. CL, Terrell. “Antifungal Agents. Part II. the Azoles.” Mayo Clinic Proceedings, U.S. National Library of Medicine.
Image Courtesy:
1. “Fluconazole skeletal formula” By Vaccinationist – PubChem (Public Domain) via Commons Wikimedia
2. “Ketoconazole enantiomers” By Vaccinationist – (2R,4S)-(+)-ketoconazole on PubChem(2S,4R)-(−)-ketoconazole on PubChem (Public Domain) via Commons Wikimedia