I. What is Tretinoin?

Also known as all-trans-retinoic acid, tretinoin is the acid form of vitamin-A. It is a crystalline powder which is yellowish in color. Retinoic acid is soluble in DMSO, Polyethylene Glycol and Ethanol. It is practically insoluble in mineral oil and water. The oral version of this acne medication is used to treat leukemia. For the treatment of acne, the topical cream or gel version is used.

II. How does Tretinoin works on acne?

In short, Tretinoin works by stimulating the skin cells to divide at a faster rate. Faster cell division means increased skin cell turnover rate causing the skin to peel which then promotes the extrusion of blackheads and whiteheads. Overall, the skin peeling unclogs blocked pores and exposes a new layer of younger skin cells. It may take 2 months or more of Tretinoin use to see an improvement in your acne.

Advantages

  • Reduction of the appearance of fine lines and wrinkles results as the layer of younger skin cells emerges at the surface.
  • Tretinoin also suppresses the pigment producing cells of the skin known as Melanocytes. The suppression of melanocytes reduces hyperpigmentation and results into an even skin tone.

Disadvantages

  • The main disadvantage of retinoid is that they cause photosensitivity. It makes the skin very sensitive to sunlight causing sunburns.
  • Takes several months to fully work.

Efficacy

  • The addition of clindamycin to tretinoin, as in CTG, enhances the comedolytic efficacy of tretinoin in moderate to severe acne of the face, maintaining at the same time its anti-inflammatory efficacy thus accelerating resolution of all types of acne lesions without affecting the safety of response to both components.
    ( Source: Richter JR, Förström LR, Kiistala UO, Jung EG., Yamanouchi Europe B.V., Medical Department Europe, Leiderdorp, The Netherlands. J Eur Acad Dermatol Venereol. 1998 Nov;11(3):227-33.)
  • Both TGM (Tretinoin Gel Microspheres) 0.04% and TGM 0.1% were associated with reductions in lesion counts in these patients with mild to moderate facial acne. Both concentrations were generally well tolerated. The results suggested an early (week 2) incremental benefit for the use of TGM 0.1% in the treatment of inflammatory lesions.
    ( Source: Berger R, Rizer R, Barba A, Wilson D, Stewart D, Grossman R, Nighland M, Weiss J., Clin Ther. 2007 Jun;29(6):1086-97)

III. Forms and Dosage

  • Prescription cream and gel @ 0.01%, 0.025%, 0.05% concentration. GEL form penetrates the skin better and is more effective compared to creams but it can be more irriating. The best form of tretinoin is the microsphere cream which is a time released version of this acne medication. The microsphere cream is the least irritating form of tretinoin. Examples of tretinoin suspended in microsphere vehicle is Retin-A® Micro and Stieva-A cream. The topical liquid form is suspended into an alcoholic base which would be more irritating.

IV. Precautions

  • Do not use other products with high levels of alcohol, menthol and other keratolytic or
    peeling agents such as salicylic acid. Do not use the product if you are pregnant or is at high risk of pregnancy. Vitamin-A and Vitamin-A related chemicals are terratogenic which means they cause malformation of fetus.

V. Side Effects

  • During the 2 weeks of use, you would experience acne breakouts and flaking of the skin. Burning sensation, redness and peeling of the skin is expected. Lightening or darkening of the skin is also expected. As your skin adjusts to the medication, the side effects would gradually be lessened. This medication would also make your skin more sensitive to the sun. It is advisable to use sunblock (at least SPF15) when going out in areas where you are exposed to the sun otherwise your skin would be severely sunburned. In case of skin flaking, use a moisturizer to minimize flaking.
  • " Dryness, redness or peeling may occur during the first weeks of treatment. To prevent aggravating the skin, protect it from sun, tanning lights, extreme wind or cold and harsh skincare products. Use of sunscreen is recommended. " (source: http://www.retinamicro.com)

Brands

Altinac™; Avita®; RENOVA®; Retin-A™; Retin-A® Micro

References

  • http://www.retinamicro.com ( 12 October 2007 )
  • http://www.nlm.nih.gov/medlineplus/druginfo/medmaster/a682437.html ( Last Revised - 04/03/2000 American Society of Health-System Pharmacists, Inc.)
  • Aditya K Gupta MD, PhD, FRCP(C), Melissa D Gover BSc, William Abramovits MD (2007)
    Ziana (Clindamycin Phosphate 1.2% and Tretinoin 0.025%)Gel
    SKINmed 6 (2), 85–87.
  • Tretinoin: A review of preclinical toxicological studies Marvin Cohen * Scientific Information Services Department, Hoffmann-LaRoche, Inc., Nutley, New Jersey
  • Effects of tretinoin on photodamaged skin. A histologic study
    J. Bhawan, A. Gonzalez-Serva, K. Nehal, R. Labadie, L. Lufrano, E. G. Thorne and B. A. Gilchrest
    Department of Dermatology, Boston (Mass) University School of Medicine 02118.

Page last modified: January 07, 2008