121 East 60th Street, Suite 8AB, New York, NY 10022

Ph. (212) 285-1110

Long Island

901 Stewart Ave, Suite 240, Garden City, NY 11530

Ph. (516) 512-7616

New York City (212) 285-1110

Garden City, NY (516) 512-7616

Photodynamic Actinic Keratosis Therapy in New York

Photodynamic therapy (PDT) is a unique treatment that is commonly used to treat acne, skin cancers, and pre-cancerous skin lesions. The treatment involves applying a photosensitizing drug (a drug that increases sensitivity to light) to the targeted lesion and then using light therapy to treat the area.

PDT Background

Physicians have recognized the power of photosensitizing drugs for thousands of years. Records from ancient Egyptian and Indian civilizations document the use of photosensitizing substances and a light source to treat certain skin lesions. It is likely that the use of PDT was discovered accidentally and that ancient physicians did not fully understand its mechanism of action.

A renewed interested in photodynamic therapy1 began in the 1960s with the development of safe and effective photosensitizing drugs. Researchers and scientists documented success in using PDT in treating actinic keratosis and certain forms of cancer. Today PDT is commonly used to treat pre-skin cancers and acne lesions. This highly effective treatment causes minimal discomfort to patients and does not leave lasting scars, making it a treatment of choice for certain skin lesions on visible areas of the body.

PDT for Acne

When Dr. Rokhsar meets with patients who are troubled by moderate to severe acne that does not respond to other treatments, he may recommend photodynamic therapy2. PDT can stop acne activity, diminish older acne scars, and leave the skin looking and feeling much smoother.

When using PDT to treat acne, Dr. Rokhsar first cleanses the skin and then applies Levulan, a unique photosensitizing drug that is very effective in the treatment of acne. After the drug has penetrated the skin (15 – 45 minutes), he turns on a special light that is calibrated to emit blue or red light, depending on the type of acne being treated. Levulan makes certain cells and the acne sebaceous glands more sensitive to light. PDT3 is such an effective acne treatment thanks to the combined use of Levulan and light therapy.

PDT for Skin Cancer & Pre-Cancerous Lesions

PDT is also a very effective and safe way of treating certain types of skin cancers and pre-cancerous lesions, including:

  • Actinic keratoses (pre-cancerous growths that occur on sun-exposed areas of the body)
  • Superficial basal cell carcinomas
  • Bowen’s disease
  • Hidradenitis suppurativa

Dr. Rokhsar preps the targeted area by thoroughly cleansing the lesion and surrounding skin. If necessary, he will remove some of the crust from the lesion so the photosensitizing drug can absorb into the skin more easily. Next, he applies the drug and allows it to soak into the skin for up to 6 hours. In certain instances, he may inject the drug into the targeted area. Once the drug has thoroughly penetrated the skin, light therapy begins. PDT may successfully eliminate the lesion on the first round or multiple treatments may be required, spaced at monthly intervals.

PDT Recovery and Side Effects

PDT is a safe and effective treatment, but it’s normal to experience certain mild side effects after treatment, which are collectively referred to as the “PDT effect.” The treated area may appear red and swollen and may feel tender or sensitive. A scab or crust usually forms after several days and many people experience discomfort during this phase. After several weeks, the scab will fall off and the skin below may appear pinker or lighter than surrounding skin. Over time, the new skin will take on its normal tone and texture as the body creates healthy new skin cells.

During the treatment, the skin became extremely sensitive to light. This sensitivity remains for the first 48 hours, so it is extremely important that patients protect the treated area from the sun during this time. This may require the use of strong sunscreen, hats, scarves, gloves, and other protective clothing. Once the first 2 days have passed, patients still need to protect their skin to prevent permanent color changes in the treated area.

Benefits of PDT

In comparison to other skin treatments, PDT offers many advantages. These include:

  • Fast treatment of acne lesions that cover large areas of the face
  • Effective acne treatment without the need for systemic drugs like Accutane
  • No scarring
  • Avoidance of surgical excision (pre-cancerous lesions and skin cancer)
  • Overall improvement in skin tone and texture including brown spots and Rosacea

PDT For Acne FAQ

How is light therapy used to cure acne?

PDT for acne is a two-step procedure that has amazing results in controlling cystic acne and preventing scar formation. First, a light absorbing agent is applied to the skin and left to penetrate for about an hour. Next, any residual substance that did not absorb into the skin is removed, and the skin is exposed to a special light. The light is attracted to the areas where the light-absorbing agent penetrated and kills the bacteria in those areas.

Is PDT light therapy painful?

Treatment with PDT light therapy at our NYC office is as comfortable as possible. A slight stinging may be felt when the light is shone on the skin, but this discomfort passes quickly.

How many sessions of PDT light therapy are needed?

PDT for acne generally requires a series of two to three treatments for best results. NYC dermatologist and laser specialist, Dr. Rokhsar spaces each session three weeks apart.

What is photodynamic therapy?

Photodynamic therapy (PDT) is a medical treatment that uses a photosensitizing agent and light to destroy cancerous or precancerous cells. This treatment is usually performed in a two-step process. First, a photosensitizer drug is administered to the patient via oral ingestion, skin application, or intravenous injection. After 24 to 72 hours, most of the drug will have left normal cells, but remain in cancer or precancer cells. Then, the cancerous or precancerous cells are exposed to a specific wavelength of light, usually from a laser, which activates the photosensitizer. This results in the production of oxygen molecules that can kill the targeted cells by inducing apoptosis, a process of programmed cell death.

Photodynamic therapy has been shown to be effective in treating a variety of medical conditions, including certain types of cancer such as skin cancer and bladder cancer. It has also been used to treat age-related macular degeneration, psoriasis, and atherosclerosis. In addition, it has shown some efficacy in antiviral treatments, including herpes.

PDT has become increasingly popular in dermatology, where it is used to treat acne and actinic keratosis, a precancerous skin condition that presents as rough, scaly patches. Photodynamic therapy can also selectively kill abnormal, potentially cancerous cells in specific areas of the skin damaged by sun exposure.

While photodynamic therapy can be effective in destroying cancerous or precancerous cells, it is not suitable for all patients and is not always curative. Patients with certain medical conditions, such as porphyria or allergies to porphyrins, cannot undergo this treatment. In addition, the effectiveness of PDT can be limited by the depth of the targeted tissue and the size of the treatment area. However, PDT has shown promise as a safe and effective therapy for certain medical conditions, and research into its potential applications continues.

What are the side effects of photodynamic therapy?

Common side effects of PDT include redness, swelling, itching, and even small blisters. The treated area of the skin is usually quite red and may appear to be flaking or peeling, as it would after a mild sunburn. The redness, and perhaps some of the flaking, can last for several days to a week or even two weeks.

Other possible side effects of PDT include swelling at or near the area of skin treated, discoloration of your skin, scales, crusts or blisters on your skin receiving treatment, itching, stinging or burning, and skin infections. Damage to normal cells is limited.

One of the most common side effects of PDT is sensitivity to bright lights and sunlight. These reactions caused by PDT light can show up on the skin where the drug is applied. They usually involve redness and a tingling or burning sensation. Additionally, some of the side effects of PDT depend on the area that is treated. For example, if PDT is used to treat esophageal cancer, side effects may include hiccups, difficulty swallowing, and nausea and vomiting.

How can photodynamic therapy treat acne?

Most short-contact PDT treatments start with microdermabrasion to remove excess dead cells on the skin’s surface and enhance the penetration of the photosensitizing agent, aminolevulinic acid (ALA). After ALA application, the skin is treated with the pulsed dye laser to activate the ALA. . Photodynamic therapy helps shrink oil glands, which in turn can reduce acne. Studies show an average of 60% reduction in acne, and results appear to last for months afterward, and perhaps long term. Dr. Rokhsar advises to do at least 3 photodynamic therapy sessions once a month. Some chose to do up to 6 sessions. The treatment is not painful, but one may feel slight discomfort during the veal laser activation of the ALA. The treatment feels like a rubber band snapping on your skin. PDT also helps the redness of acne as well as acne scars.

New York Office Locations

Upper East Side Manhattan Office
121 East 60th Street, Suite 8AB New York, NY 10022
(212) 285-1110

Long Island Office
901 Stewart Ave, Suite 240, Garden City, NY 11530
(516) 512-7616

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  1. Photodynamic Therapy. Available:
  2. Photodynamic Therapy. Available:
  3. Photodynamic Therapy (PDT): PDT Mechanisms. Available:

About author - Dr. Cameron Rokhsar

Dr. Cameron Rokhsar

Dr. Cameron Rokhsar, MD, FAAD, FAACS, is the founder and medical director of the New York Cosmetic, Skin, & Laser Surgery Center. Dr. Rokhsar is a graduate of Harvard College and NYU School of Medicine. Dr. Rokhsar is double board certified in dermatology and micrographic dermatologic surgery, being one of the few select dermatologists in the country who is also fellowship trained in laser surgery. A researcher and innovator, Dr. Rokhsar is the creator of the non-surgical nose job and has been instrumental in the research and development of laser systems such as the Fraxel, CO2, Mirady, Vbeam, Themitight, and Ulthera devices. An Associate Professor of Dermatology at Mount Sinai Hospital in NYC, Dr. Rokhsar actively teaches the cosmetic dermatology clinic to the resident at Mount Sinai. An expert injector of fillers, and a trainer for many companies, patients fly in from around the world to see Dr. Rokhsar in his Garden City and Manhattan offices in New York.

Learn more about Dr. Rokhsar | Dr. Rokhsar's Google Scholar