erythromycin + tretinoin: clinical use

Prescribing considerations

• Confirm pregnancy and breastfeeding status and pregnancy intentions.
• Review other topical preparations and irritants used on affected skin.
• Counsel about photosensitivity, eye avoidance and flammability.
• Avoid excessive application or use over a damaged skin barrier.

Contraindications and cautions

• Hypersensitivity to erythromycin, tretinoin or an excipient
• Pregnancy or planning pregnancy
• Acute eczema, rosacea or acute inflammatory skin disease, particularly around the mouth
• Sunburn affecting the proposed treatment area
• Family history of cutaneous epithelioma
• Concomitant topical skin medicines, particularly keratolytic agents

Monitoring

• Assess redness, burning, dryness and peeling.
• Review persistent deterioration, marked irritation or suspected allergic contact eczema.
• Stop treatment and assess urgently for features of acute generalised exanthematous pustulosis.
• Observe for temporary lightening or darkening of treated skin.

Clinical pharmacology

Topical erythromycin has bacteriostatic and anti-inflammatory activity. Tretinoin increases turnover and shedding of follicular epithelium, reducing comedonal obstruction. Dermal erythromycin absorption is described as negligible; some tretinoin absorption can occur.

Formulation and product differences

• The selected product is a clear cutaneous solution in an amber bottle with a foam-pad applicator.
• It contains ethanol, glycerol and copolyvidone. Ethanol may sting damaged skin and makes the product flammable.
• Keep the bottle in its outer carton to protect it from direct sunlight.