BRAND NAMES
- International: Isotrexin
 MECHANISM OF ACTION
Erythromycin is a macrolide antibiotic produced by Streptomyces erythraeus. it binds to the 50S ribosomal subunit, inhibiting bacterial protein synthesis.
Erythromycin penetrates into the ducts of the sebaceous glands of the skin and unflods its specific effect at this site against bacterias which are involved in the development of acne.
Isotretinoin is the 13-cis isomer of Tretinoin.
Topical tretinoin decreases cohesiveness of follicular epithelial cells with decreased microcomedo formation. Additionally, tretinoin stimulates mitotic activity and increased turnover of follicular epithelial cells causing extrusion of the comedones.
Topical treatment of acne vulgaris
Apply sparingly over the entire affected area once or twice daily.
Patients should wash their hands after application of the gel.
Patients should be advised that, in some cases, six to eight weeks of treatment may be required before the full therapeutic effect is observed.
Patients should be advised that if Erythromycin/Isotretinoin topical gel is applied excessively, no more rapid or better results will be obtained and marked redness, peeling or discomfort may occur. If this occurs accidentally, or through over enthusiastic use, application should be discontinued for a few days.
- Known hypersensitivity to isotretinoin or to erythromycin
- Pregnancy, women intending to conceive and lactation
- Patients with a personal or family history of skin cancer.
 WARNINGS AND PRECAUTIONS
- Colitis: As with other broad spectrum antibiotics, pseudomembranous colitis has been reported rarely with erythromycin. Although this is unlikely to occur with topically applied erythromycin, if prolonged or significant diarrhoea occurs or the patient suffers from abdominal cramps, treatment should be discontinued immediately and the patient investigated further, as the symptoms may indicate antibiotic-associated colitis.
- Ultraviolet Light and Environmental Exposures: Avoid exposure to sunlight and sunlamps. Wear sunscreen daily. Wear sunscreen daily
- Use with caution in patients with concomitant rosacea or perioral dermatitis, due to the irritant nature of isotretinoin.
- Concomitant application of oxidising agents, such as benzoyl peroxide, should be avoided, since they may reduce the efficacy topical isotretinoin. If combination therapy is required, they should be applied at different times of the day, e.g. one in the morning and the other in the evening. If irritancy or dermatitis results, the frequency of application may have to be reduced.
 PREGNANCY AND LACTATION
- Isotretinoin has been associated with teratogenicity in humans when administered systemically. Erythromycin/Isotretinoin topical gel is contraindicated in pregnant women or those who may become pregnant during treatment.
- Nursing Mothers: Percutaneous absorption of isotretinoin and erythromycin from Erythromycin/Isotretinoin topical gel is negligible. However, as it is not known if isotretinoin is excreted in human milk, Erythromycin/Isotretinoin topical gel should not be used during lactation.
 SIDE EFFECTS
Erythromycin/Isotretinoin topical gel may cause:
Immune System Disorders
Skin and subcutaneous tissue disorders
Stinging, burning sensation, pruritus or skin irritation; erythema, dry skin, skin exfoliation; skin thinning, skin hyperpigmentation, skin hypopigmentation and photosensitivity reaction.
If undue irritation occurs, treatment should be interrupted temporarily and resumed once the reaction subsides. If irritation persists, treatment should be discontinued. Reactions will usually resolve on discontinuation of therapy.
 RELATED LINKS
|Oral antibiotics||Clindamycin (Oral route) • Doxycycline • Erythromycin (Oral route) • Josamycin • Lymecycline • Minocycline • Tetracycline|
|Topical antibiotics||Clindamycin (Topical) • Erythromycin (Topical)|
|Topical retinoids||Adapalene • Tazarotene • Tretinoin|
|Oral retinoids||Isotretinoin (Oral)|
|Oral contraceptives||Estradiol valerate/Dienogest • Ethinyl Estradiol/Cyproterone acetate|
|Topical Antibacterial/Keratolytic||Benzoyl peroxide • Hydrogen Peroxide Cream|
|Topical combination products||Clindamycin/Benzoyl peroxide • Adapalene/Benzoyl peroxide • Clindamycin/Tretinoin • Miconazole/Benzoyl peroxide • Erythromycin/Benzoyl peroxide • Erythromycin/Isotretinoin|