Acne, psoriasis, rosacea, skin cancers…there seems to be no shortage of skin conditions. Yet sadly, all of these skin conditions impact our self-confidence and self-esteem leaving us hunting for the best treatments, creams, or pills.

I see patients all the time who tell me that they have “tried everything.” Or they have done so much research they don’t know where to start. So, there is a good chance that you may have already heard about photodynamic therapy (PDT). 

Also known as red light therapy (RLT), blue light therapy, or low-level light therapy, PDT is an emerging treatment for several dermatological skin conditions. So, before you jump right into PDT treatment, let’s review my essential guide to photodynamic therapy.

Photodynamic Therapy

Have you seen celebrities sporting glowing masks on social media? Or, have you had an advertisement pop-up for an LED mask touting its ability to improve your skin’s appearance? These therapies might seem a little crazy, but the truth is, they can help enhance your skin’s appearance and treat several skin conditions.

Photodynamic Therapy 

Photodynamic therapy (PDT) is a powerful in-office treatment most commonly used to target and kill both cancerous and precancerous cells using red or blue light. PDT is used to treat several other skin conditions, including reducing the appearance of acne, scars, redness, and wrinkles. 

It may seem odd to think about shining a light on the skin after we’ve talked so much about sun protection and sunscreen. But unlike the UVA rays found in tanning beds or from the sun, the light used in PDT does not damage your skin or cause sunburns. 

Conditions Treated by Photodynamic Therapy

The FDA approves PDT for the treatment of precancerous cells, also known as actinic keratoses. Still, there is promising research using PDT as the treatment for some common skin conditions, including:

  • Promotion of wound healing
  • Improving acne and acne scarring
  • Reducing wrinkles, fine lines, and age spots
  • Improving psoriasis, rosacea, and eczema
  • Boosting collagen production
  • Stimulating hair growth and follicle health
  • Improving sun-damaged skin

How does PDT work?

Specific cells absorb light wavelengths stimulating them to work by providing the cell’s “power plant” (the mitochondria) with more energy helping those cells to work more efficiently. When exposed to light therapy, these cells can help the skin to boost new cell growth, stimulate collagen production, increase blood circulation, and reduce cellular inflammation.

PDT uses a drug activated by light, called a photosensitizer, that creates a sort of target for the light, telling it where to go and what to focus on. Once the photosensitizer is absorbed by the targeted cells, light is applied to the area to activate the medication.

What’s the difference between blue light and red light PDT?

The difference between blue light and red light PDT is all about how deep the light penetrates the skin. Blue light only penetrates the skin about 0.5mm, whereas red light can penetrate between 2 to 3mm. 

Blue light may be an excellent option depending on the depth of treatment needed. But, blue light is not always a good treatment option for skin cancer or acne because of its poor penetration into the skin.  

What can I expect during a PDT treatment?

After the photosensitizer absorbs, the light source is applied to the impacted area. When treating the face, you’ll sit in front of a U-shaped fluorescent lamp. During light exposure, patients can experience discomfort, including a tingling or a mild burning sensation. Some offices provide a cooling option, or you can pause treatment momentarily. The pain and discomfort should subside once the light source is off.

How many PDT treatments will I need?

The number of PDT treatments depends on what type of skin condition you are treating. Precancerous cells and skin cancers are commonly treated two to three times. Cosmetic PDT treatments for acne, scarring, fine lines, and wrinkles may require more treatments to experience long-lasting benefits. 

What can I expect after a PDT treatment?

The treated skin is usually pink or red with some discomfort for up to 48 hours following a PDT treatment. It’s also not uncommon for the skin to flake, peel, weep, or scab, lasting from several days to a week or even two after treatment.

Here are a few additional considerations for after a PDT treatment:

Light Sensitivity

One of the most common side effects of PDT is sensitivity to sunlight. For some time after treatment, you’ll need to avoid exposing any treated areas to bright lights or sunlight. And remember that sunscreen will not protect the skin from photosensitivity reactions but should be worn to help protect skin from further UVA exposure.

I recommend the following:

  • Avoid intense, direct light
  • Stay indoors as much as possible
  • When outside, wear protective clothing and hats

Skin Changes

Depending on the type and location of treatment, the skin may swell or blister after treatment lasting from a few hours to a few days. 

Additional skin changes may include:

  • Burning or Itching
  • Change in the color of the skin or a loss of pigmentation
  • Scarring (typically mild to moderate)
  • Skin infections

Patients typically experience a full recovery in seven to 10 days and may begin wearing make-up within 48 hours as long as there are no open sores. 

How do I get started with PDT?

It’s best to check in with your dermatologist about the best options to treat your skin concerns before beginning treatment. But don’t be afraid to ask about how PDT might benefit you. If you’re ready to try PDT, remember that it is not a one-time treatment for most skin issues. Treatments need to be done consistently to get the best results. 

You’ll also find many light therapy products available for purchase. While these products are generally safe, they frequently use a lower wavelength frequency (making them less powerful) than the devices used by a dermatologist. So, you may not experience the results that you were hoping for. 

Heal Your Skin Inside and Out

Learn how your skin integrates with your mind, body, and spirit and begin healing your skin from the inside and out. Discover more about integrative dermatology and how you can have the clear skin you desire with my SkinClock Method.

Limited spots are available. 

Join my waitlist today and start your journey to healthy, glowing skin.



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