Tretinoin solution

Charge items 1 to 5 in a suitable stainless steel-jacketed vessel heat to 40° to 50°C to obtain a clear solution. 

In a separate jacketed vessel, charge item 6 and heat to 90° to 95°C. 

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Some active substances are so sensitive to light that light must be excluded to the highest possible extent during preparation. In practice, this means that the preparation should not be done in the vicinity of a window and that artificial lights should be switched off. Examples of pharmaceutical preparations for which this may be necessary are dithranol cream, phytomenadione oral solution and tretinoin solution. 

Tretinoin was compared with glycolic acid in ten Indian women with melasma, an acquired symmetrical hypermelanosis characterized by irregular light to gray-brown macules on sun-exposed skin that is more frequently seen in women and is more prevalent in darker complexioned individuals [308]. In this study, a 1 % tretinoin peel was applied on one side of the face weekly for 12 weeks, and 70 % glycolic add was appUed similarly to the other side. The tretinoin solution contained 1 % tretinoin in a 95 % isopropyl alcohol base and 5 % chloroform with antioxidant butylated hydroxy-toluene. There was a significant decrease in the melasma score from 6 to 12 weeks, with no difference between the tretinoin- and glycolic-acid-treated sides. Side effects were minimal and tretinoin was well tolerated [308]. 

In commenting on Khunger et al. s [308] study, Kligman [309] notes that the pH of the tretinoin (all-trans retinoic acid) solution is approximately 6.0 and that, unlike TCA and glycolic acid, does not cause epidermal neaosis [309]. Rather, tretinoin causes a delayed peeling action due to an inflammatory response [309]. A 0.25 % tretinoin solution in 50 % ethanol and 50 % polyethylene glycol 400 has also been used [310]. 

Figure 9.3 Application of the skin tone tretinoin solution...

TCA 10-30% Tretinoin Salicylic Acid Glycolic Acid Jessner s Solution... 

Tretinoin Retin-A Retin-A Micro 0.025%, 0.05%, and 0.1 % cream 0.01%, 0.025% gel 0.05% solution 0.04% and 0.1% gel Apply a small amount once daily before bedtime Skin irritation, dryness, photosensitivity initially may worsen acne Skin irritation, dryness, photosensitivity initially may worsen acne... 

There are many types of preparations that contain retinol. Absorption is greatest for aqueous preparations, intermediate for emulsions, and slowest for oil solutions. Whereas oil-soluble preparations may lead to greater hepatic storage of the vitamin, water-miscible preparations usually provide higher concentrations in plasma. Vitamin A is available as capsules. Tretinoin (all-trans-retinoic acid Retin A) is available for topical use. Isotretinoin (13-ri.s-retinoic acid Accutane) is available for oral use, as is etretinate (Tegison). 

The products usually used to prepare the skin are sunscreens, tretinoin, AHAs and tyrosinase inhibitors. Jess-ner s solution is sometimes used as a pre-peel preparation. It is often necessary to take measures to prevent infection, especially herpes. 

Either the applicator provided with the product or the point of a 30G1/2 needle should be used to limit the action precisely to the head of the comedone. In 95% of cases, comedolysis is achieved. Very large macrocomedones (>2 mm in diameter) can benefit from careful infiltration of Easy TCA or Easy Phytic solution into the center of the comedone. Post-peel care, which is very important, consists in avoiding comedogenic cosmetics, having the skin cleansed professionally once a month, and applying an antiacne cream containing AHAs, tretinoin or precursors, disinfectants, anti-inflammatories, tea-tree oil, etc." once or twice a day. For details of this treatment, see Chapter 15. 

Tretinoin is available as 0.05% solution (most irritating), 0.01% and 0.025% gels, and 0.025%, 0.05%, and 0.1% creams (least irritating). Treatment initiation with 0.025% cream usually is recommended for mild acne in patients with easily irritated and nonoUy skin, 0.01% gel for moderate acne in easily irritated skin with oily complexion, and 0.025% gel for moderate acne with nonsensitive and oily skin. A flare of acne may appear suddenly after initiation of treatment, followed by clinical clearing in about 8 to 12 weeks. ... 

Adapalene, a derivative of naphthoic acid, is a synthetic retinoid-like compound that is available in solution, cream, and gel formulations for topical use. In addition to displaying typical retinoid effects, it also has antiinflammatory properties. Adapalene has similar efficacy to tretinoin, but unlike tretinoin, it is stable in sunlight and tends to be less irritating in nature. 

Tan, X. Meltzer, N. Lindenbaum, S. Solid-state stability studies of 13-cis-retinoic acid and all-tmns-retinoic acid using microcalorimetry and HPLC uialysis. Pharm.Res., 1992,9,1203-1208 [solutions simultaneous degradation products, isotretinoin, tretinoin]... 

Ferry JJ, Forbes KK, VanderLugt JT, Sqiunar GJ. Influence of tretinoin on the percutaneous absorption of minoxidil from an aqueous topical solution. CUn Pharmacol Ther (1990) 47, 439-46. 

Glycolic acid Jessner s solution Pyruvic acid Resorcinol Salicylic acid Trichloroacetic acid Tretinoin Malic acid Deep chemical peels... 

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