Mequinol/tretinoin

The combination of mequinol and tretinoin, mequinol/tretinoin, is a prescription solution used for the treatment of solar lentigines. Solar lentigines are commonly referred to as "sun" spots; these spots commonly appear as medium to dark brown areas on the hands, face, forearms and chest of most fair-skinned people in middle age. The Food and Drug Administration approved mequinol/tretinoin on December 10, 1999. Mequinol/tretinoin was developed by Galderma Labs and is marketed by Barrier Therapeutics under the name Solage.

Other Names

Mequinol is also called 4-hydroxyanisole and tretinoin is also called all-trans-retinoic acid.

Uses

Mequinol/tretinoin is used for the treatment of solar lentigines or "sun spots".

How Mequinol/tretinoin is Taken

Mequinol/tretinoin is supplied as solution that is applied to the skin (a topical solution). The solution is 2% Mequinol and 0.01% tretinoin. It is applied directly to the solar lentigines using the applicator tip without applying it to the surrounding skin. Some physician instructions may differ, but typically Mequinol/tretinoin is applied once in the morning and once at night, separated by at least eight hours. The solution can be washed off during bathing or showering. To avoid this, people can bathe or shower at least six hours after treatment.

How Mequinol/tretinoin Works

The mequinol component is believed to bind to the enzyme tyrosinase and prevent melanin production. Melanin is the compound that gives skin its color. In this way, tyrosine inhibition prevents skin darkening.

The mechanism of action of the tretinoin component in reducing skin coloring is unknown.

How the Body Affects Mequinol/tretinoin

One study showed that only about 4.5% of tretinoin is absorbed into the body through the skin.^[1] Similarly, very little Mequinol is absorbed.

Side Effects

Below are the most frequent side effects in people treated with Mequinol/tretinoin:

• skin redness
• burning, stinging, or tingling of skin
• shedding of skin
• itching
• skin irritation
• temporary hypopigmentation (lightening of skin)

Risks and Precautions

• Mequinol/tretinoin can harm the eyes, mouth, nose, and mouth if applied to these areas.

• Mequinol/tretinoin is used with caution in people with a history, or family history, of the skin condition vitiligo.

• Application of larger amounts of medication than recommended will not lead to better results and may worsen the side effects.

• Mequinol/tretinoin he combination of mequinol and tretinoin may cause fetal harm when administered to a pregnant woman.

Drug Interactions

Other topical products or procedures with a strong skin drying effect may cause skin irritation when given with mequinol/tretinoin. Some of these products and procedures include the following:

• products with high concentrations of
  • alcohol
  • astringents
• spices or lime
• medicated soaps or shampoos
• permanent wave solutions
• electrolysis
• hair depilatories or waxes

Mequinol/tretinoin is not used in combination with drugs that sensitize the skin to sunlight or bright indoor light. Many antibiotics sensitize the skin to bright light.

Research

Two trials evaluated the change in pigmentation of skin on the face, forearms/back of hands in 421 patients treated with mequinol/tretinoin , 422 patients treated with tretinoin alone, 209 patients treated with mequinol alone, and 107 patients treated with placebo for up to 24 weeks. ^[2] Mequinol/tretinoin lightened skin gradually over the study period. At 24 weeks of treatment, 57% and 54% of the Mequinol/tretinoin-treated patients experienced moderate improvement or greater, and 3% and 1% of these patients were completely clear of all treated lesions for the face and forearms/back of hands, respectively.

In another study involving non-Caucasians, over 80% of treated subjects achieved a significant response to Mequinol/tretinoin therapy for facial and arm lesions. ^[3]

References

1. ↑ Everett DW, Franz TJ, Chando TJ, et al. Percutaneous absorption of [3H]tretinoin and systemic exposure to mequinol after dermal application of 2% mequinol/0.01% [3H]tretinoin (Solagé) solution. Biopharm Drug Dispos. 1999 Sep;20(6):301-8. Abstract
2. ↑ Food and Drug Administration Web site. Package Insert Solage. PDF
3. ↑ Draelos ZD, Spreen K. Phase 4 trail findings on the safety and tolerability of combination solution of meguinol 2%/tretinoin 0.01% in dark skin types (Poster) American Academy of Dermatology Summer (Academy ‘06) Meeting. PDF

External Links

• FDA: Patient Information Sheet