The skin has the ability to absorb various substances. Some penetrate the most superficial layers and others, the deepest layers of the organ, and can even enter the bloodstream. The penetration of cosmetic substances, for example, is not always possible due to natural barriers – such as the stratum corneum (outermost layer of the skin, made up of keratin). A new technique, called drug delivery, has been proposed to help the penetration of topical products into the internal layers. It consists of "delivering" medication to the skin immediately after using an ablative laser or microneedling, creating opening channels, which facilitates the absorption of the drug. The subject has been discussed worldwide for some years, but only more recently has the technique been used as one of the best alternatives. O drug delivery It can be adopted for rejuvenation, stretch marks, scars, melasma, hair loss, etc. Dermatologist Luiza Pitassi, coordinator of the Cosmetics Outpatient Clinic at Hospital de Clínicas (HC), says that the drug delivery has been used at Unicamp through treatment protocols in the area of Cosmetics and that, soon, new studies will be developed (through the elaboration of clinical protocols) for the use of this technique in the treatment of skin cancer, the most prevalent in Brazil . The doctor provides some information about the technique in an interview given to Unicamp website. Read below.
Unicamp Portal - What is the purpose of the drug delivery?
Luiza - It is a technique that consists of using methods to increase skin permeability and improve skin penetration of medications. Medication absorption faces a major challenge, which is the skin's barrier function, which limits the absorption of many active ingredients. Only a few molecules have the ability to cross this barrier, and the cutaneous bioavailability of most drugs is low, ranging from 1 to 5%.
Unicamp Portal - How has it been used?
Luiza - Recently, the use of lasers as promoters of drug delivery has demonstrated excellent results in delivering medications to the skin in a uniform and controlled manner. Ablative lasers (CO2 10.600nm and Erbium YAG 2940nm) create microchannels in the skin called thermal microzones that help with this work.
Another method of tissue ablation associated with the drug delivery It is performed using fractionated radiofrequency with needles. In this procedure, energy is applied using thin electrodes on the skin, with the formation of micropores that allow the transport of drugs and macromolecules, being used for the same indications as ablative lasers.
Another example is the use of procedures with microneedling devices by rolling needles into the skin, creating conduits that allow substances (from small molecules to macromolecules) to penetrate. These microchannels facilitate efficient drug delivery and can increase the absorption of larger molecules by up to 80%. Immediately after the procedure, the drug delivery with application of the active ingredients through a massage for two minutes in the treated areas.
Recently, a new technique called microinfusion of medicines into the skin (MMP®) has been used to treat various dermatological diseases. This technique permeates medicines into the dermis effectively and precisely through a machine that uses microneedles, in back and forth movements, with controlled speeds and depths.
Unicamp Portal - Is this something new in Brazil? And, in other countries, as has been the use of drug delivery?
Luiza - Yes, it is a new treatment that has been studied and carried out recently in Brazil, with several clinical protocols for the treatment of dermatological diseases. This technique provides an increase in the number of active ingredients that can be efficiently transported through the skin, with increasing importance in Dermatology. Most studies related to the use of laser and drug delivery are carried out with the participation of Rox Anderson, main researcher in the field of laser and photomedicine at Harvard Medical School, United States.
Unicamp Portal - What have been the indications?
Luiza - In cosmiatry, the most common indications for drug delivery They are for the treatment of melasma, wrinkles, sagging, traumatic scars, stretch marks, acne scars and hair loss. This technique has also been used in the treatment of skin cancer. Photodynamic therapy (PDT) is an effective treatment for superficial non-melanoma skin cancers, actinic keratosis, but thicker lesions are more resistant to treatment due to the low penetration depth of photosensitizing medications. Pre-treatment with laser on affected skin has been shown to increase the penetration of these photosensitizing agents, improving the effectiveness of treatment through the technique of drug delivery.
Unicamp Portal - What are the most used substances for drug delivery with laser?
Luiza - In general, these are vitamin C, E, ferulic acid, hyaluronic acid, polylactic acid, retinoic acid, botulinum toxin, methotrexate, 5-fluorouracil (5-FU), imiquimod, ingenol mebutate, minoxidil, growth factors, 5-acid aminolevulinic and methylaminolevulinate.
Unicamp Portal - Is the treatment painless? Is it equivalent to surgery?
Luiza - The treatment is not completely painless, but it is well tolerated by patients. A topical anesthetic cream is applied to the area to be treated one hour before the procedure to reduce pain and discomfort. Depending on the indication and the specific clinical condition, treatment can be carried out with infiltrative anesthesia or, sometimes, even under sedation in a surgical center. Patients must be advised to carry out the procedure with a specialist doctor, and it is essential that it takes place in a medical environment and that appropriate antisepsis protocols are followed.
Unicamp Portal - Does this procedure replace others?
Luiza - It is complementary to the treatment of various dermatological diseases. The technique of drug delivery enhances the results of already standardized treatments, facilitating the permeation of topical products into the inner layers of the skin and favoring a faster and more efficient response. In addition to being a promising technique for treating diseases that are difficult to resolve, there is a great advantage of reducing the cost of treatment, by using a precise amount of the drug and increasing the therapeutic response.
Unicamp Portal - What are your contraindications?
Luiza - The main contraindications for invasive procedures, where skin rupture occurs, are the use of systemic anticoagulants, bleeding disorders, d uncontrolled, collagen diseases and skin infection in the area to be treated. People using isotretinoin and immunosuppressants are also contraindicated in undergoing the procedure during treatment.
Unicamp Portal - The technique drug delivery Can it be recommended for children and the elderly?
Luiza - Yes, in the treatment of dermatological diseases, but the ideal is to seek out a dermatologist specialized in the Brazilian Society of Dermatology, so that he can evaluate each case and suggest the most appropriate treatment.
Unicamp Portal - What precautions should be taken after the procedure?
Luse - Immediately after any of the procedures associated with the drug delivery Burning, bleeding, edema and a slight reddish hue may occur, which can last between two and five days, depending on the technique used and the individual response of each patient.
