Clotrimazole

Clotrimazole

General Description:

Clotrimazole is a broad-spectrum antifungal agent, effective particularly against Candida albicans and many other fungi. It works by inhibiting the synthesis of fungal cell membranes and disrupting their metabolic processes. It is effective against both superficial and certain deep fungal infections.

Clinically, it is mainly used topically to treat fungal infections such as athlete’s foot (tinea pedis), ringworm (tinea corporis), otomycosis (fungal ear infections), and vaginal yeast infections.
Due to its high systemic toxicity, oral administration may cause gastrointestinal irritation, liver function abnormalities, and leukopenia, and is now rarely used orally.
Topical application is generally well-tolerated, with rare occurrences of localized irritation or inflammation. Topical forms are typically in 1%–3% creams or suppositories.

Basic Information:

• Chinese Name: 克霉唑

• Other Chinese Name: 1-[(2-氯苯基)二苯甲基]咪唑

• English Name: Clotrimazole

• CAS No.: 23593-75-1

• EINECS No.: 245-764-8

• Molecular Formula: C₂₂H₁₇ClN₂

• Molecular Weight: 344.84 g/mol

• Exact Mass: 344.108

• Topological Polar Surface Area (PSA): 17.82

• LogP: 5.3767

Physicochemical Properties:

• Appearance: White or slightly yellow crystalline powder

• Odor/Taste: Odorless and tasteless

• Solubility:

  • Easily soluble in methanol and chloroform

  • Soluble in ethanol and acetone

  • Nearly insoluble in water

• Melting Point:

  • General: 147–149°C

  • According to Pharmacopeia (2010, Appendix VI C): 141–145°C

• Boiling Point: 482.3°C at 760 mmHg

• Flash Point: 245.5°C

• Refractive Index: 1.616

• Density: 1.13 g/cm³

• Vapor Pressure: 5.42E-09 mmHg at 25°C

• Storage Conditions: Store at room temperature (RT)

Pharmacology & Toxicology:

Clotrimazole is an imidazole-class antifungal drug with significant inhibitory effects on a broad range of fungi, including:

• Trichophyton rubrum

• Trichophyton mentagrophytes

• Cryptococcus neoformans

• Aspergillus spp.

• Candida albicans (most effective)

Mechanism of Action:

• Inhibits the activity of cytochrome P-450 enzymes in fungi

• Blocks ergosterol biosynthesis (a key component of fungal cell membranes)

• Disrupts cell membrane integrity and increases permeability, leading to leakage of essential intracellular components

• Inhibits the biosynthesis of triglycerides and phospholipids

• Inhibits oxidase and peroxidase activity, causing accumulation of hydrogen peroxide, leading to cellular structure damage and fungal cell death

• Particularly effective in preventing Candida spore transformation into invasive hyphal forms

Uses:

Used in antifungal dermatological medications, both for superficial and deep fungal infections, such as:

• Cryptococcal meningitis

• Pulmonary and intestinal candidiasis

• Histoplasmosis

• Ringworm (Tinea corporis)

• Athlete’s foot (Tinea pedis)

Note: It is ineffective against scalp fungal infections (tinea capitis) whether used topically or orally.