How does retina work

One of the most successful patents of all time, it revolutionized topical skin care and still has great utility today. To understand how Retin-A works, it helps to understand the effects of aging on the skin. The most superficial cells — the keratinocytes of the epidermis — tend to become more adhesive and hang around longer. This leaves the skin looking dryer and rougher.

The epidermal cells at the base also do not replicate as quickly, so the lifespan of these cells in the outer layer is much longer — and it shows. The pigmentation can become irregular and mottled because of this. The deeper layer of cells, called the dermis, and the collagen bundles become thinner and disordered, allowing for creases and fine wrinkles to more easily show the muscular activity from below. Retin-A is a topical medicine available by prescription only that is applied sparingly to the facial skin, sparing the eyelids and the corners of the nose and lips.

It works at the cellular level and takes several months to see the full effect. In many ways, Retin-A can be thought of as reversing the outwards signs of aging on the skin. The earliest effect of Retin-A is that the outer layer of keratinocytes start shedding off, leaving the skin fresher, smoother and more evenly pigmented.

The next effect seen is that the epidermal cells start to replicate faster causing the skin to look and feel softer, more robust and healthier. Finally, the collagen bundles in the dermis will thicken and organize, causing the appearance of fine lines and wrinkles to lessen with time. Mobile Newsletter chat subscribe. Prev NEXT. Everyday Innovations.

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Lab studies involving human skin samples suggest that it not only increases cell turnover but also activates a cell type responsible for secreting collagen, a protein that gives skin its elasticity.

Studies in humans have shown that it may increase thickness of the outer skin layer epidermis and help minimize facial wrinkles after 12 weeks of use. These benefits may be greatest in people who experience photoaging , the premature aging of the skin caused by excessive exposure to UV radiation. Because of its potential for skin irritation, Retin-A is typically used to treat conditions like hyperpigmentation or photoaging, rather than for aesthetic purposes.

It is also often used in combination with hydroquinone and topical corticosteroids. As such, Retin-A may not be the best option if you're simply looking for an anti-aging cream.

Retinol , found in many over-the-counter creams and serums, is vitamin A in topical form. Retin-A is a synthetic derivative of vitamin A that is stronger and requires a prescription. While gentler on the skin, retinol has only mild anti-acne effects and is not as effective in reducing wrinkles as tretinoin and other retinoic acids. Retin-A should be used under medical supervision as part of a comprehensive acne treatment plan. This should include using of an effective sunscreen minimum SPF 15 , wearing sun-protective clothing, and avoiding excessive sunlight exposure.

If you use another over-the-counter or prescription acne remedy, let your healthcare provider know before starting treatment. More is not necessarily better when it comes to treating acne. In some cases, you may need to take a break from your current acne medications before starting Retin-A.

You should also walk your healthcare provider through your daily skincare routine. Because Retin-A can cause skin irritation, your healthcare provider or dermatologist may recommend a change like using a different cleanser, astringent , or exfoliant. You will need to avoid Retin-A if you have a known hypersensitivity to tretinoin or any other ingredient in the product.

Retin-A should should also be avoided in people with eczema atopic dermatitis or sunburned skin, as it can cause severe irritation. Retin-A should not be prescribed to children under 12 in whom the safety has not been established and the drug may be too harsh.

Although there's no clear evidence that topical tretinoin causes birth defects, oral tretinoin has been linked to this risk. It is not known whether the drug is excreted in breast milk. People who are breastfeeding or pregnant should only Retin-A if the benefits outweigh the possible risks.

An in-depth conversation with a healthcare provider is needed to make an informed choice. Retin-A should be used with caution in people who are pregnant or breastfeeding and ideally after consultation with a healthcare provider or dermatologist.

Do not Retin-A on children under There are other tretinoin-based topical drugs used to treat acne. The choice of drug may be based on the severity of your acne and the condition of your skin. There are two similar drugs approved for use by the FDA:. A related drug called Accutane isotretinoin is taken by mouth and used to treat severe inflammatory acne. Retin-A is applied to the skin daily and delivers the best results when used consistently.

The drug is available in three forms:. It generally takes two to three weeks before you begin to see the benefits of Retin-A treatment. In some cases, it can take six weeks or more. Retina-A is used once daily before bedtime.

Apply enough to cover the affected area lightly. Putting on a thick layer will not improve results and may only increase skin irritation. Avoid applying Retin-A around the corners of the eyes, nose, or mouth.

You should not apply it to open wounds, as this can cause pain and inflammation. Protect your skin from the sun, wind, and cold, as it will be more sensitive to the elements for several months after starting tretinoin.

Daily sunscreen is advised. Retin-A cream, gel, and liquid can be stored safely at temperatures under 80 degrees F. The medication does not require refrigeration but can be refrigerated if there is a risk of excessive heat exposure. Refrigerated Retin-A can also be soothing to the skin. Retin-A gel is flammable. Keep the gel well away from open flames, and do not expose it to temperatures over degrees F. Keep the tube tightly sealed and out of the reach of children. Discard any expired drugs.