Propionibacterium acnes is a Gram-positive organism that resides
in the pilosebaceous glands in skin. Together with abnormal
keratinization of the follicles causing plugging, sebaceous oil
production and hormones, P. acnes is a cause of acne.
P. acnes produces porphyrins, mainly coproporphyrin III, in the pilosebaceous follicles and these porphyrins are potential targets for photodynamic therapy. Visible blue light at a wavelength of 405-420 nm and visible red light at 570-670 nm have been shown to stimulate porphyrins to release singlet oxygen which destroys P. acnes. This treatment can be helpful in mild to moderate acne. There are no side effects, no downtime and bacterial resistance is unlikely. Blue or red light can be used once or twice a week for 20 minutes for about 3 months. Maintenance treatments can be done as needed.
With the addition of a photosensitizing medication such as Levulan or Metvix in moderate to severe acne, more porphyrins are produced for a greater reduction in P. acnes. These medications also shrink the sebaceous glands, decrease sebum production, and increase the turnover of epidermal cells, unplugging the follicles.
The photodynamic procedure is commonly performed in my office by my technicians. I
determine the length of time the medication stays on the skin and the amount of time the patient is exposed to the light source. The skin is scrubbed well with acetone, the photosensitizing medication is applied and left on the skin for 1 to 3 hours. The patient then sits in a dimly lit small room and can read, text or listen to music. If Levulan is used, we use a blue light for activation. The patient wears protective eyewear and sits in front of the blue light for approximately 10 to 14 minutes. The face is then washed and sunscreen is applied. If Metvix is used, the medication is washed off before the treatment and the patient is exposed to the red light for 10 minutes. Sunscreen is then applied.
Regardless of which medication is used, 5 treatments, 3 weeks apart are recommended. The patient must avoid sun exposure for the first 36 hours since the medication can continue to activate with light and give a more intense reaction than desired. The usual side effects are redness, peeling and some crusting for about 3 to 5 days. Patients wash with a mild cleanser and use an oil-free moisturizer and sunscreen.
Many patients will remain clear of acne for many months or indefinitely. Topical medication may be necessary to maintain the effects of treatment in some patients. Repeat treatments can be done as needed.
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P. acnes produces porphyrins, mainly coproporphyrin III, in the pilosebaceous follicles and these porphyrins are potential targets for photodynamic therapy. Visible blue light at a wavelength of 405-420 nm and visible red light at 570-670 nm have been shown to stimulate porphyrins to release singlet oxygen which destroys P. acnes. This treatment can be helpful in mild to moderate acne. There are no side effects, no downtime and bacterial resistance is unlikely. Blue or red light can be used once or twice a week for 20 minutes for about 3 months. Maintenance treatments can be done as needed.
With the addition of a photosensitizing medication such as Levulan or Metvix in moderate to severe acne, more porphyrins are produced for a greater reduction in P. acnes. These medications also shrink the sebaceous glands, decrease sebum production, and increase the turnover of epidermal cells, unplugging the follicles.
The photodynamic procedure is commonly performed in my office by my technicians. I
determine the length of time the medication stays on the skin and the amount of time the patient is exposed to the light source. The skin is scrubbed well with acetone, the photosensitizing medication is applied and left on the skin for 1 to 3 hours. The patient then sits in a dimly lit small room and can read, text or listen to music. If Levulan is used, we use a blue light for activation. The patient wears protective eyewear and sits in front of the blue light for approximately 10 to 14 minutes. The face is then washed and sunscreen is applied. If Metvix is used, the medication is washed off before the treatment and the patient is exposed to the red light for 10 minutes. Sunscreen is then applied.
Regardless of which medication is used, 5 treatments, 3 weeks apart are recommended. The patient must avoid sun exposure for the first 36 hours since the medication can continue to activate with light and give a more intense reaction than desired. The usual side effects are redness, peeling and some crusting for about 3 to 5 days. Patients wash with a mild cleanser and use an oil-free moisturizer and sunscreen.
Many patients will remain clear of acne for many months or indefinitely. Topical medication may be necessary to maintain the effects of treatment in some patients. Repeat treatments can be done as needed.
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