Tretinoin belongs to the drug group of retinoids. The active ingredient is used as a cream or lotion to treat acne, so that the skin appearance returns to normal and the disease is treated in the long term.
What is tretinoin?
Tretinoin belongs to the drug group of retinoids. The active ingredient is used as a cream or lotion to treat acne
Tretinoin is a vitamin A acid that softens the horny layer of the skin and prevents infections of the sebaceous glands and the reformation of pustules, papules, nodules and comedones (blackheads). Closed blackheads open and repel the horny plug. Other ingredients and excipients include glycerol distearate, glycerol monostearate, polyglycol fatty alcohol ether, magnesium sulfate 7 H2O, cetyl ester wax, butylated hydroxyanisole, edetic acid and disodium salt 2 H;O.
Pharmacological action
The drug is applied to the skin once or twice daily. Dead cells are dissolved from the cornea to allow the diseased skin to heal. Tretinoin stimulates cell renewal, prevents keratinization and infection of the sebaceous glands, and inhibits the growth of tumor cells. Before starting treatment, the doctor explains to the patient that the therapy will take place over a longer period of several weeks. After the first four weeks of treatment, the patient is asked for a check-up and, depending on the clinical effect and side effects, continues to be observed at longer intervals. After clinical healing, pubertal acne requires preventive further treatment over several months or even years before the clinical picture disappears completely. After the first eight to 14 days of treatment, there is a renewed apparent flare-up of acne, which is due to an increased formation of blackheads with subsequent pustule formation. This is a so-called initial worsening, which occurs with many medications. It is the physician’s task to point out this process to the patient during the initial discussion. For better tolerability, tretinoin is available in new carrier substances as polymers and microsponges. These reduce the potential for irritation.
Medical application and use
Tretinoin is available as a lotion and cream (Airol) and as 10 mg capsules (Vesanoid). A concentration of 0.05 percent of the active ingredient in creams and lotion is common. The clinical picture treated includes mild to moderate acne disorders that occur predominantly on the face. These are acne comedonica and acne papulopustulosa, which are characterized by blackheads, inflammatory skin changes, papules, reddened skin changes as well as pustules and pustules. As a cream or lotion, tretinoin is applied thinly to the affected areas of skin twice daily with a cotton ball. For fair and sensitive skin, the substance is applied once a day. It should not come into contact with mucous membranes and eyes and should not be applied too close to the lips. As a rule, the number of blackheads decreases within a treatment period of three to five weeks. A lasting therapeutic effect is achieved after six to 14 weeks, which depends on regular use as prescribed. The drug can also be used for acne manifestations that occur as a side effect of other medications. However, the success of treatment has not been scientifically proven. In capsules, the active substance is used in high dosage of 10 milligrams for treatment of acute promyelocytic leukemia, a special form of myeloid acute leukemia. The doctor sets the dose depending on the patient’s height, weight and health condition. The recommended daily dose is 45 mg/m2 of body surface area, which corresponds to a daily dose of eight capsules in two equal single doses. If there are other diseases to be treated, the daily dose should be adjusted accordingly. Tretinoin is combined with cytostatics and increases the patient’s chance of survival by seventy percent in contrast to cytostatic therapy alone. Furthermore, the drug reduces the risk of disease recurrence.
Risks and side effects
Tretinoin is contraindicated in eczema, perioral dermatitis, rosacea, and hypersensitivity to the active ingredient. This hypersensitivity includes allergic reactions to other representatives of retinoids.A cross-reaction exists with antibiotics from the tretracycline group, which may cause visual disturbances, headache, respiratory dysfunction, and increased intracranial pressure. Nausea, vomiting and transient unconsciousness are other side effects. During the first four weeks of treatment, there is an increased risk of thrombosis. Therefore, tretinoin should not be taken concomitantly with medications that promote blood clotting. Severe courses include liver dysfunction, lipid metabolism disorders, fever, sweating, anxiety, cardiac arrhythmias, pancreatitis, water retention in the lungs, and kidney, liver, and multiple organ failure. In the case of reactive proliferation of white blood cells, a clinical picture occurs which is similar to leukemia, but is not leukemia. The drug should not be used during pregnancy due to an increased risk of miscarriage and malformations. Among the characteristic malformations is the retinoid syndrome, in which the child has a head that is too small and a brain that is not formed according to age (microcephaly). A severe mental handicap or reduced intelligence can then be assumed. Other physical malformations may also occur. The drug should also not be used during breastfeeding. In children, there is not yet sufficient evidence, so the benefits and risks must be carefully weighed. Interactions also exist with other acne medications. Commonly observed side effects include local skin irritation, skin redness, rash, skin detachment, dry skin, inflammation, discoloration, itching, hyperkeratosis, and hyperpigmentation. Tretinoin can also cause photosensitization. The skin is sensitive to sunlight. When used in capsule form, the drug may decrease the effectiveness of contraceptive medications. The patient must refrain from taking vitamin A preparations and other retinoid substances at the same time, since in interaction they increase the previously mentioned adverse drug reactions. Regular blood monitoring is required. Vesanoid capsules for the treatment of promyelocytic leukemia must not be taken during concomitant therapy with antibiotics such as rifampicin and erythromycin, glucocorticoids, phenobarbital, cimetidine, ciclosporin, and aminocaproic acid, tranexamic acid, and aprotinin.
