Itraconazole is a broad-spectrum antifungal medicine belonging to the triazole class. It is used to treat a wide range of fungal infections affecting the skin, nails, lungs, and internal organs. The medicine works by inhibiting fungal cell membrane synthesis, thereby stopping fungal growth and gradually clearing the infection. Itraconazole is commonly prescribed for moderate to severe fungal infections that do not respond adequately to topical therapy and for infections requiring systemic treatment.

Itraconazole is a potent triazole antifungal agent with activity against dermatophytes, yeasts, and moulds. Fungal infections occur when pathogenic fungi invade the skin, mucous membranes, nails, or deeper tissues, often thriving in warm and moist environments or in individuals with weakened immunity. Conditions such as chronic skin infections, nail fungus, oral and vaginal candidiasis, and serious systemic fungal infections can significantly affect quality of life if left untreated.

Itraconazole acts by disrupting the synthesis of ergosterol, an essential component of the fungal cell membrane. Without ergosterol, the fungal cell membrane becomes unstable and leaky, leading to impaired growth and eventual death of the fungus. Unlike topical antifungals that work only on the surface, Itraconazole is absorbed into the bloodstream and reaches deeper tissues, hair follicles, and nail beds, making it highly effective for persistent or extensive infections.

Itraconazole is widely used in the treatment of fungal nail infections (onychomycosis), tinea infections (such as ringworm, athlete’s foot, and jock itch), and systemic fungal infections like aspergillosis and histoplasmosis. It is also used in immunocompromised patients who are at higher risk of invasive fungal infections.

The medicine is usually taken after food to improve absorption and should be taken exactly as prescribed. Treatment duration varies depending on the type and severity of infection, ranging from a few weeks for skin infections to several months for nail or systemic infections. Even if symptoms improve early, completing the full course is essential to prevent recurrence and resistance.

Patients taking Itraconazole are often monitored for liver function and potential drug interactions, as Itraconazole can affect liver enzymes and alter the metabolism of other medicines. With appropriate medical supervision, Itraconazole plays a vital role in effectively treating fungal infections and restoring health.

Itraconazole is indicated for the treatment of:

Superficial Fungal Infections of the Skin:

Used to treat dermatophyte infections such as ringworm (tinea corporis), athlete’s foot (tinea pedis), and jock itch (tinea cruris) when topical therapy is ineffective or unsuitable.

Fungal Nail Infections (Onychomycosis):

Effective in treating infections of the fingernails and toenails caused by dermatophytes and yeasts.

Mucosal Fungal Infections:

Used for oral, oesophageal, and in some cases vaginal candidiasis, particularly when other antifungal treatments have failed.

Systemic and Deep-Seated Fungal Infections:

Indicated for serious infections such as aspergillosis, histoplasmosis, blastomycosis, and sporotrichosis, especially in immunocompromised patients.

Prevention and Treatment of Fungal Infections in High-Risk Patients:

Prescribed for patients with weakened immune systems who are at increased risk of invasive fungal infections.

1. Broad-Spectrum Antifungal Activity:

Itraconazole is effective against a wide range of fungi, including dermatophytes, yeasts, and moulds, making it suitable for multiple fungal conditions.

2. Deep Tissue Penetration:

The medicine accumulates in keratin-rich tissues such as skin, hair, and nails, ensuring prolonged antifungal action even after treatment completion.

3. Effective for Nail Fungal Infections:

Itraconazole is one of the most effective oral treatments for onychomycosis, especially when topical therapy has failed.

4. Suitable for Systemic Infections:

It treats serious fungal infections involving the lungs or internal organs, which cannot be managed with topical agents.

5. Reduced Risk of Recurrence:

By eliminating fungi at deeper levels, Itraconazole lowers the chance of infection returning when taken for the full prescribed duration.

6. Convenient Oral Therapy:

Available as oral capsules, Itraconazole allows systemic treatment without hospitalisation in many cases.

Itraconazole is generally well tolerated when used as prescribed, but some side effects may occur.

Common Side Effects (Usually Mild)

• Nausea
• Abdominal pain
• Diarrhoea
• Headache
• Dizziness
• Mild skin rash

Less Common Side Effects

• Loss of appetite
• Indigestion
• Fatigue
• Altered taste sensation

Serious Side Effects (Seek Immediate Medical Attention)

• Signs of liver damage: Yellowing of skin or eyes, dark urine, pale stools, persistent nausea
• Severe allergic reactions: Swelling of face, lips, tongue, difficulty breathing
• Heart failure symptoms: Shortness of breath, swelling of ankles, sudden weight gain
• Severe skin reactions (very rare): Blistering or peeling of skin

• Take Itraconazole exactly as prescribed by your doctor.
• It should be taken after a full meal to enhance absorption.
• Swallow the capsule whole with water.
• Do not crush or chew the capsule.
• Take the medicine at the same time each day for best results.
• Complete the full course even if symptoms improve early.

Itraconazole is a systemic antifungal medicine that works by disrupting the structure and function of fungal cell membranes, which are essential for fungal survival and growth.

• Systemic Distribution: After oral administration, Itraconazole is absorbed into the bloodstream and distributed widely to body tissues, including the skin, lungs, mucous membranes, and keratin-rich areas such as hair and nails, allowing it to treat both superficial and deep-seated fungal infections.
• Inhibition of Ergosterol Synthesis: Itraconazole inhibits the fungal enzyme lanosterol 14-α-demethylase, a key component of the cytochrome P450 system required for the synthesis of ergosterol.
• Cell Membrane Disruption: Ergosterol is a vital structural component of the fungal cell membrane. Inhibition of its production leads to weakened and leaky cell membranes, impairing fungal cell integrity and function.
• Growth Inhibition and Fungal Death: The altered cell membrane prevents normal fungal growth (fungistatic effect) and, at higher concentrations or with prolonged exposure, can result in fungal cell death (fungicidal effect).
• Prolonged Tissue Retention: Itraconazole accumulates and persists in keratinised tissues such as nails and skin even after treatment ends, providing sustained antifungal activity and reducing the risk of relapse.

• Always take after meals.
• Do not skip doses.
• Avoid alcohol during treatment.
• Complete the full treatment course.
• Keep skin and nails clean and dry.
• Regular blood tests may be required for long courses.

• Store below 25°C.
• Protect from moisture and light.
• Keep out of reach of children.
• Do not use after expiry date.

• Should be taken with food to improve absorption.
• Acid-suppressing agents (antacids, proton pump inhibitors) may reduce absorption.
• Avoid grapefruit juice as it may increase Itraconazole levels.

• Statins (e.g., Simvastatin, Atorvastatin): Concomitant use with Itraconazole may significantly increase statin blood levels due to enzyme inhibition, raising the risk of muscle toxicity, including myopathy and rhabdomyolysis.
• Calcium Channel Blockers (e.g., Verapamil, Diltiazem, Amlodipine): Itraconazole can increase the blood levels of these medicines, potentially leading to low blood pressure, swelling, or worsening of heart failure.
• Oral Anticoagulants (e.g., Warfarin): Itraconazole may enhance the anticoagulant effect, increasing the risk of bleeding.
• Benzodiazepines (e.g., Midazolam, Triazolam): Co-administration may result in prolonged sedation and respiratory depression due to reduced drug breakdown.
• Immunosuppressants (e.g., Cyclosporine, Tacrolimus, Sirolimus): Itraconazole can markedly increase blood concentrations of these drugs, increasing the risk of toxicity.
• Antiarrhythmic Drugs (e.g., Quinidine, Dofetilide): Combined use may increase the risk of serious heart rhythm disturbances and is generally contraindicated.
• Acid-Suppressing Agents (Proton Pump Inhibitors, H₂ Blockers, Antacids): These medicines can reduce Itraconazole absorption by lowering stomach acidity.
• Certain Antiepileptics (e.g., Phenytoin, Carbamazepine): These may reduce Itraconazole levels, decreasing its effectiveness.

• Liver disease: Increased risk of hepatotoxicity
• Heart failure: Contraindicated due to negative inotropic effects
• Kidney disease: Use with caution
• Immunocompromised states: Requires close monitoring

The dose depends on the infection:

• Skin infections: 200 mg once daily for 1–4 weeks
• Nail infections: 200 mg daily or pulse therapy as prescribed
• Systemic infections: 200–400 mg daily under specialist supervision

Always follow your doctor’s instructions.

Symptoms may include nausea, vomiting, dizziness, and abdominal pain. Seek immediate medical attention. Treatment is supportive.

Take the missed dose as soon as you remember. If it is almost time for the next dose, skip the missed dose. Do not double the dose.