Isdiben (Isotretinoin)

• Isotretinoin is a systemic retinoid that acts on the sebaceous gland pathway to treat severe forms of acne.
• Severe recalcitrant nodular acne: reduces existing inflammatory lesions, prevents new nodule formation, and markedly decreases sebum production.
• Severe acne vulgaris: improves both inflammatory and non‑inflammatory lesions when other therapies have failed.
• Acne conglobata: helps control extensive nodular disease and reduces cystic lesion development.

• Isotretinoin binds to nuclear retinoic acid receptors (RARs) in keratinocytes and sebaceous gland cells, modulating gene expression that leads to reduced sebocyte proliferation, decreased sebum synthesis, and normalization of follicular keratinization. It also exerts anti‑inflammatory effects by down‑regulating pro‑inflammatory cytokines, thereby limiting the bacterial colonisation that contributes to acne lesions.

Isotretinoin may cause a range of adverse reactions that vary in frequency and severity.

Common Side Effects

• Dry skin and mucous membranes, including cheilitis.
• Xerosis (dryness) of eyes and nasal passages.
• Photosensitivity and increased sunburn risk.
• Elevated serum triglycerides and cholesterol.
• Transient headache or visual disturbances.
• Musculoskeletal discomfort or arthralgia.

Serious or Rare Side Effects

• Severe depression, suicidal ideation, or mood changes.
• Inflammatory bowel disease (ulcerative colitis or Crohn's disease).
• Hepatotoxicity with elevated liver enzymes.
• Teratogenic effects causing major fetal malformations.
• Severe hypertriglyceridemia leading to pancreatitis.
• Pseudotumor cerebri (intracranial hypertension).

Before initiating therapy, clinicians should assess baseline laboratory values and counsel patients on safety measures.

• Pregnancy: Contraindicated in pregnancy; ensure reliable contraception for both sexes.
• Teratogenicity: Avoid use in women of child‑bearing potential without effective birth control.
• Laboratory monitoring: Check liver function tests and lipid profile before and during treatment.
• Vitamin A intake: Do not combine with other vitamin A derivatives or supplements.
• Mood monitoring: Observe for signs of depression or suicidal thoughts.
• Store at ambient temperature: Keep below 25°C in the original container, protect from moisture and light.

Isotretinoin can interact with several medicines, altering efficacy or increasing toxicity.

Major Interactions (Avoid)

• Tetracycline antibiotics: Increased risk of intracranial hypertension.
• Vitamin A supplements: Additive retinoid toxicity.
• Systemic corticosteroids: May diminish isotretinoin effectiveness.

Moderate Interactions (Monitor Closely)

• Oral contraceptives: Potential reduction in contraceptive efficacy; advise additional barrier methods.
• Anticoagulants (e.g., warfarin): May affect INR; monitor coagulation parameters.
• Lipid‑lowering agents (statins): Possible alteration of lipid levels; observe lipid profile.