Usage
Amorolfine is prescribed for the treatment of mild to moderate fungal nail infections (onychomycosis), specifically distal and lateral subungual onychomycosis caused by dermatophytes, yeasts, and molds. It’s effective against a broad spectrum of fungi. Pharmacologically, it is classified as a topical antifungal agent. Amorolfine works by inhibiting the biosynthesis of ergosterol, a crucial component of the fungal cell membrane. This disruption leads to altered membrane permeability and function, ultimately resulting in fungal cell death.
Alternate Names
While “amorolfine” is the internationally recognized generic name, the drug is marketed under various brand names, including Loceryl, Omicur, and others. Regional variations in the name may exist, but “amorolfine” remains the most common.
How It Works
Pharmacodynamics: Amorolfine exerts its antifungal effect by targeting ergosterol biosynthesis within the fungal cell membrane. The mechanism of action involves the inhibition of two key enzymes in the ergosterol pathway: Δ14-reductase and Δ7-Δ8-isomerase. This inhibition results in the depletion of ergosterol and the accumulation of abnormal sterols, thus disrupting membrane integrity and function, leading to fungal cell death. No receptor binding or neurotransmitter modulation is involved.
Pharmacokinetics: When applied topically as a nail lacquer, amorolfine penetrates the nail plate and reaches therapeutic concentrations in the nail bed. Systemic absorption is minimal, minimizing the risk of systemic side effects. Elimination pathways are not clinically relevant due to the low systemic absorption. Metabolism information regarding CYP enzymes is not significant for topical application.
Dosage
Standard Dosage
Adults:
Apply the nail lacquer to the affected nails once or twice weekly. The frequency can be adjusted to twice weekly if deemed clinically necessary. Before the first application, the affected areas of the nail should be filed down as much as possible using a single-use nail file provided in most commercial kits, then cleansed with the provided cleaning pad or cotton wool. This process needs to be performed every time before application. Using the applicator provided, apply amorolfine evenly to the entire surface of the infected nail(s). Do not allow amorolfine to come into contact with the surrounding skin. The nail lacquer should not be applied on the skin around the nail. The solution should be allowed to dry (approximately 3-5 minutes) before covering. After drying, the treated nails can be washed with soap and water. Artificial nails should not be used during treatment. Cosmetic nail polish can be applied but should be removed before Amorolfine is reapplied. Fingernail infections are typically treated for 6 months, and toenail infections for 9 to 12 months.
Children:
Amorolfine nail lacquer is not recommended for use in children under 18 years due to the lack of clinical data on safety and efficacy in this population.
Special Cases:
- Elderly Patients: No specific dosage adjustments are required for elderly patients.
- Patients with Renal Impairment: No dosage adjustment is necessary due to negligible systemic absorption.
- Patients with Hepatic Dysfunction: No dosage adjustment is necessary due to negligible systemic absorption.
- Patients with Comorbid Conditions: Patients with diabetes or peripheral circulatory disorders should consult a physician before using amorolfine. Caution is advised for patients with compromised immune systems.
Clinical Use Cases
The dosages provided above are for the treatment of onychomycosis. Amorolfine nail lacquer is not indicated for intubation, surgical procedures, mechanical ventilation, ICU use, or emergency situations.
Dosage Adjustments
No specific dosage adjustments are routinely made based on renal/hepatic dysfunction, metabolic disorders, or genetic polymorphisms.
Side Effects
Common Side Effects
- Nail discoloration
- Brittle or broken nails
- Skin irritation around the treated nail (burning, itching, redness)
Rare but Serious Side Effects
Severe allergic reactions (rash, itching, swelling, difficulty breathing) are rare but require immediate medical attention.
Long-Term Effects
No specific long-term effects have been reported with topical amorolfine use.
Adverse Drug Reactions (ADR)
Clinically significant ADRs are rare but include severe allergic reactions and contact dermatitis.
Contraindications
- Known hypersensitivity to amorolfine or any of the excipients in the formulation.
Drug Interactions
No significant drug interactions have been reported with topical amorolfine. However, concomitant use with other topical medications applied to the same area is not recommended as it can alter the absorption of the active substance. When organic solvents are used, impermeable gloves shall be worn to protect the Amorolfine Nail Lacquer on the nails, otherwise it will be removed.
Pregnancy and Breastfeeding
Data on the use of amorolfine during pregnancy and breastfeeding are limited. Due to minimal systemic absorption following topical application, the risk to the fetus or nursing infant is theoretically low. However, as a precaution, use during pregnancy and breastfeeding is generally avoided unless deemed clearly necessary by a physician.
Drug Profile Summary
- Mechanism of Action: Inhibits ergosterol biosynthesis, disrupting fungal cell membrane integrity and function.
- Side Effects: Nail discoloration, brittleness, skin irritation, rarely allergic reactions.
- Contraindications: Hypersensitivity to amorolfine.
- Drug Interactions: None clinically significant reported.
- Pregnancy & Breastfeeding: Avoid unless clearly necessary.
- Dosage: Apply to affected nails once or twice weekly for 6 months (fingernails) or 9-12 months (toenails).
- Monitoring Parameters: Observe the affected nail for signs of improvement or adverse reactions.
Popular Combinations
Topical amorolfine is typically used as monotherapy. Co-existent tinea pedis should be treated with an appropriate antimycotic cream.
Precautions
- General Precautions: Assess for hypersensitivity before use. Advise patients to avoid contact with eyes, ears, and mucous membranes.
- Specific Populations: As outlined above for pregnant/breastfeeding women and children.
- Lifestyle Considerations: No specific restrictions on alcohol, smoking, or diet. No impact on driving ability.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Amorolfine?
A: Apply to the affected nails once or twice a week.
Q2: How long does treatment typically last?
A: 6 months for fingernails and 9-12 months for toenails.
Q3: Can I use cosmetic nail polish during treatment?
A: Yes, but remove it before each amorolfine application. Allow the amorolfine to dry for at least 10 minutes before applying cosmetic nail polish.
Q4: What should I do if I miss a dose?
A: Apply the missed dose as soon as you remember. If it is close to your next dose just continue with the regular dosing regime. Do not apply a double dose to make up for a missed one.
Q5: What are the most common side effects?
A: Nail discoloration, brittleness, and mild skin irritation around the nail.
Q6: Is amorolfine safe during pregnancy?
A: While the risk is low, use during pregnancy should be avoided unless deemed absolutely necessary by a physician.
Q7: How does amorolfine work?
A: It inhibits the synthesis of ergosterol, a crucial component of the fungal cell membrane. This disruption weakens the fungus and inhibits its growth eventually leading to its death.
Q8: Can amorolfine be used for all types of nail fungus?
A: It is most effective for mild to moderate distal and lateral subungual onychomycosis and it might not be effective if the lunula is involved. If the infection is severe, consult a doctor.
Q9: What if my symptoms don’t improve after using amorolfine?
A: If there is no improvement after 3 months, or if the condition worsens, consult a doctor. They can perform a full assessment.
