Actinic Keratosis

What is Actinic Keratosis?

Actinic Keratosis (plural: Actinic Keratoses, AK) are premalignant lesions of the skin that, when left untreated, can potentially develop into skin cancer. The primary cause for AK is chronic sun damage and an estimated number of 58,000,000 Americans are currently affected with it.1 There are different stages of AK, ranging from mild over moderate to severe, being more or less scaly and varying in color from skin color to reddish or brown. AKs often occur as multiple lesions on skin areas frequently exposed to the sun, e.g. the face, scalp, neck, ears and hands.


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Who is affected with Actinic Keratoses?

Since the damage caused by frequent sun exposure is accumulated over many years, people in the second half of their life are most frequently affected with actinic keratoses (age 40 and older). The fact that tanning has been very popular for decades has led to an increase in AK with more and more people being affected as they grow older. But not only sun worshippers are at risk. Even if you have not been sunbathing, simple outdoor activities, e.g. gardening, walks in the sun or working outside, can amount to enough damage that may put you at risk for AK. In particular fair skinned people and those with a compromised immune system, e.g. organ transplant recipients, are more likely to develop AKs.1


who is affected gekauft


Why treat Actinic Keratoses?

AK is the most frequent precancer. It can potentially develop into squamous cell carcinoma (SCC), the second most common skin cancer, which can become life threatening if untreated and may require surgery.1 A retrospective study has shown that in up to 10% of AK patients, individual AK lesions progressed to SCC within an average of two years.2 Therefore, treating AK during the early stages is a safe and effective way of reducing the risk of AK progression to skin cancer.


AK progression
The progression of actinic keratosis to squamous cell carcinoma, a serious type of non-melanoma skin cancer, primarily caused by UV light (e.g. sunlight).

What does Actinic Keratosis look and feel like?

In the early stages, actinic keratoses may not be very prominent when looking in the mirror. More frequently, these so called “sun spots”, also known as lesions or plaques, are felt as a rough surface, similar to that of sandpaper. Early AKs may be easier felt than seen. The skin may be scaly and of red or brownish color. This appearance can be accompanied by itching. The size of a plaque can range from as small as a freckle to the size of a thumbnail or larger. As the disease progresses, multiple actinic lesions can cover larger areas of the skin, on the surface and beneath, resulting in premalignant fields.


AK stages Actinic keratoses of varying severity
Actinic keratoses of varying severity on the face and scalp ranging from mild to moderate. Multiple lesions may cover a larger area of skin, resulting in premalignant fields.

What are premalignant fields?

While some AK lesions are visible and felt on the skin surface, often this is just the tip of the iceberg, with a larger portion of the skin being affected by underlying lesions in the inner layers of the epidermis.

Because sun exposure is not limited to a single spot on the skin, the damage is usually spread over a larger area with multiple actinic keratoses developing over time. The occurrence of multiple actinic lesions in larger areas of skin is very common. That is the reason why, in addition to a lesion-directed treatment, a field-directed therapy is also available.

It is possible to visualize the underlying damage as part of the field-directed photodynamic therapy, by a technique called fluorescence imaging. Mainly the premalignant cells absorb the photosensitizing drug which can be visualized with a black light after a 3-hour incubation step and prior to the red light illumination.


field cancer imaging
Fluorescence imaging after 3 hours of incubation with Ameluz®. The red fluorescent spots visualized with black light just prior to illumination show the uptake of Ameluz® in premalignant cells with actinic damage.
1 Skin Cancer Foundation  2 Fuchs A, Marmur E, Dermatol Surg. 2007 Sep; 33(9):1099-101 3 Ameluz® Prescribing Information. For Ameluz® full Prescribing Information and BF-RhodoLED® user manual please visit

Important Safety Information

Active Ingredient (in each tube):  AMELUZ® (aminolevulinic acid hydrochloride) 

Purpose: Photosensitizing agent

Uses: AMELUZ® gel, a porphyrin precursor, in combination with photodynamic therapy using BF-RhodoLED® lamp, is used for lesion-directed and field-directed treatment of actinic keratoses of mild-to-moderate severity on the face and scalp.


Do not use if you have a:

  • Known hypersensitivity to photoactive substances known as porphyrins.
  • Known hypersensitivity to soybeans
  • Known hypersensitivity to any component of AMELUZ®.

Ask your health care provider before use if you have:

  • Porphyria (hereditary disease that is characterized by abnormal production of a red blood pigment called heme).
  • Photodermatoses (skin conditions caused by or made worse by exposure to light or ultraviolet radiation).

When using this product:

  • Transient Amnestic Episodes: Photodynamic therapy may cause transient amnestic episodes (temporary loss of memory). If observed, the therapy must be stopped immediately. If observed after treatment, contact your health care provider.
  • Risk of Eye Injury: Patients and health care providers must wear protective eyewear while operating BF-RhodoLED®
  • Photosensitivity: Avoid sun exposure on the treated lesion sites and surrounding skin for approximately 48 hours following treatment
  • Risk of Bleeding: Special care should be taken to avoid bleeding during lesion preparation in patients with inherited or acquired coagulation disorders. Bleeding must be stopped before application of the gel.
  • Ophthalmic Adverse Reactions: Avoid applying AMELUZ® into the eyes. Wash eyes with water in case of accidental contact.
  • Mucous Membrane Irritation: Avoid direct contact of AMELUZ® with the mucous membranes. Wash with water in case of accidental contact.
  • Concomitant use of the following medications may increase the intensity of adverse reactions after light exposure related to photodynamic therapy: St. John’s wort, griseofulvin, thiazide diuretics, sulfonylureas, phenothiazines, sulphonamides, quinolones, and tetracyclines.

Most common adverse reactions were:

  • skin reddening
  • scaling of the skin
  • pain/burning
  • scabbing
  • irritation
  • hardening
  • swelling
  • blistering
  • itching

Most side effects occurred during illumination or shortly afterwards, were generally of mild or moderate intensity, and lasted for 1 to 4 days in most cases; in some cases they persisted for 1 to 2 weeks or even longer.

Pregnancy Warning: There is no available data on AMELUZ® use in pregnant women to inform a drug associated risk.

Lactation Warning: There is no available data regarding the presence of the active ingredient (aminolevulinic acid hydrochloride) in human milk, or the effects of aminolevulinic acid hydrochloride on the breastfed infant or on milk production.

Pediatric Warning: Safety and effectiveness in pediatric patients below the age of 18 has not been established.

Geriatric Warning: No overall differences in safety or effectiveness were observed between older (65 years and older) and younger patients, but greater sensitivity of some older individuals cannot be ruled out.


  • AMELUZ® is administered only by a health care provider.
  • AMELUZ® is for topical use only.
  • Photodynamic therapy with AMELUZ® involves preparation of lesions, application of the product, occlusion and illumination with BF-RhodoLED®
  • Retreat lesions that have not completely resolved 3 months after the initial treatment.

Inactive Ingredients: xanthan gum, soybean phosphatidylcholine, polysorbate 80, medium-chain triglycerides, isopropyl alcohol, dibasic sodium phosphate, monobasic sodium phosphate, propylene glycol, sodium benzoate and purified water.

Other Information: Store in a refrigerator, 2°C – 8°C (36°F – 46°F). Excursions permitted to 15°C – 30°C (59°F– 86°F). The risk information provided here is not comprehensive.

To learn more, talk about AMELUZ® with your health care provider. The FDA approved product labeling can be found at

You are encouraged to report side effects of Ameluz®. Please contact Biofrontera Inc. at 1-844-829-7434 or FDA at 1-800-332-1088 or