This is a common question for those who are new to using a retinoid like Tretinoin. This question also applies to those who have adjusted to their strength. The advantage of using a tailored formula of tretinoin is that it is available in different strengths.
What is Tretinoin?
Tretinoin is a derm-grade retinoid that smooths and exfoliates the skin while reducing oil production and acne and fighting sun damage. It is a more effective retinoid than its cousin retinol, which you can find in many over-the-counter products. Tretinoin will offer a better improvement in skin tone, texture, and appearance. Although it may generally be more drying, a moisturizer and sunscreen offset this as discussed here.
You may wonder what the right strength of Tretinoin is for your skin. Picking the right strength will create visible results and minimize side effects. While many may think that a higher strength is better, it is important to review the history and science of Tretinoin before considering what is best for each individual’s skin.
Tretinoin strength studies
Tretinoin comes in a variety of strengths or percentages. Initial studies of Tretinoin from the 1980s used Tretinoin 0.1% to evaluate the efficacy of Tretinoin for the treatment of photoaging. Later studies evaluated Tretinoin 0.05%. While both were equally effective over a one year period, Tretinoin 0.1% was able to achieve cosmetic improvement in 6 months while 0.05% required closer to 12 months. Finally, 0.025% was compared to 0.1% and it was found that both produced similar improvements in photoaging. However, tretinoin 0.025% caused fewer side effects such as drying and irritation. All of these studies used Tretinoin in a cream base.
These studies suggest that a higher strength Tretinoin may not always be necessary to achieve significant results. However, these studies do suggest that the strength of Tretinoin can affect how quickly improvement in the skin is noted. While all strengths were equivalent at 1 year, higher strength tretinoin products achieve results quickly, but with more side effects such as dryness, irritation, redness, and sun sensitivity. Therefore, it could be concluded that while all strengths are effective, the time taken to achieve the cosmetic result can differ, as can the side effects. For individuals with sensitive skin or high sun exposure, it may be beneficial to use lower strength tretinoin products to improve the skin while protecting it from irritation.
Tretinoin strength is only one piece of the puzzle. Another important consideration is the formulation or base of the formula. All skin products consist of an active ingredient, such as Tretinoin, and a vehicle. Depending on the vehicle, it can make the formulation more stable and enhance its effectiveness. The choice of vehicle can be just as important as the choice of strength.
Once you achieve your ideal strength and formulation of tretinoin, it is reasonable to continue with that product. The ideal strength and formulation create the desired cosmetic effect of improved skin tone and texture while minimizing side effects. There is likely no greater benefit to using a higher percentage or different vehicle, as studies have shown that they have similar outcomes over a different period of time.