I. Principles of topical drug treatment
(a) When the lesion area does not exceed 5% of the body surface area, topical treatment can be the main therapy for psoriasis, but when the lesion area is larger, it should be combined with systematic or/and ultraviolet treatment. There are more kinds of drugs for topical treatment, which can be used alone or in combination with various topical drugs.
(b) Acute phase should not use irritating drugs. Misuse of irritating drugs can enlarge the lesions and even induce erythrodermic or pustular psoriasis.
(3) Stronger drugs with better permeability can be used in the quiescent period. The concentration should be low at the beginning, and then increase as appropriate. After the skin lesions have basically subsided, the concentration of drugs with low concentration can also be used to consolidate the treatment. If the lesions are widespread, topical drugs are easily absorbed and can cause poisoning, it is advisable to apply different drugs to the lesioned areas or to change different drugs frequently.
(4) Pay attention to preventive treatment: the purpose of topical therapy is to cure each attack of psoriasis and prolong its remission period as much as possible. In order to prevent and reduce recurrence and prolong the remission period, treatment should not be stopped immediately when the skin lesions subside and clinical healing is achieved, but should continue to consolidate treatment for 1~2 months.
II. Commonly used topical drugs
(a) Keratin exfoliators and skin lubricants can remove the scales of skin lesions, relieve itching and protect the skin from cracking pain, commonly used keratin exfoliators such as 2.5-10% salicylic acid ointment, low concentration for the progressive stage of psoriasis, high concentration for the stationary stage; skin lubricants commonly used are lanolin petroleum jelly ointment, 5% boric acid ointment, 10% urea ointment, etc., mainly used for the progressive stage or erythrodermic lesions. 10% urea ointment is a kind of keratin exfoliator, which has the function of increasing the hydration of skin proteins, stopping itching, softening scales and promoting the penetration of skin, and can be used in combination with various drugs.
(B) tar preparations is a relatively old class of drugs, experience shows that the efficacy of these drugs is certain, but the disadvantages are odor, pollution of clothing, can cause folliculitis, acne, phototoxic reactions and irritant dermatitis, etc.. Purified coal tar (such as 1% pure coal tar lotion, Zeta lotion) preparations were once commonly used in China and had good efficacy on head psoriasis, but unfortunately, these preparations have stopped being sold in China since 2006.
(iii) Anthralin, also known as dithranol, has been used for the treatment of psoriasis since 1916 and has been clinically proven to have good efficacy, but it is not easily accepted by patients due to its local irritation and easy staining.
(iv) Vitamin D3 derivatives Because of its low bioavailability and not easily absorbed transdermally, it has fewer adverse effects. The development of topical topical preparations of vitamin D3 derivatives for the treatment of psoriasis became one of the important advances in the treatment of psoriasis in the 1990s and is the first-line drug for mild to moderate plaque psoriasis, especially for those who are ineffective or have reactions to other preparations that cannot be applied. There are three kinds of drugs that have been marketed so far, namely carbotriol (trade name Darex) ointment and application, tacrolimus ointment (trade name Mengfu) and osteochondriol ointment.
(E) topical retinoic acid drugs Retinoic acid drugs have been used in the treatment of dermatological diseases for more than 40 years and are known as “opening up a new era in the treatment of dermatological diseases”. In recent years, the development has been particularly rapid, and it has become one of the main drugs currently used in the treatment of psoriasis. Commonly used drugs are: 0.1% and 0.025% of retinoic acid cream, 0.05% of tazarotene gel (trade name: kynurenine) and 0.1% of tazarotene cream (trade name: Lowe).
(vi) Corticosteroids Corticosteroids have a long history of application in the topical treatment of psoriasis and have the advantages of high efficacy, rapid onset of action and a wide range of types for easy selection, etc. They are still one of the most commonly used methods in the clinical treatment of common psoriasis. Corticosteroids mainly play a therapeutic role through anti-inflammation, anti-proliferation and immunosuppression, but they should not be used on a large scale and for a long time.
There are many types of topical corticosteroids, and the efficacy of topical hormone preparations are divided into 5 levels in order of their strength on vasoconstriction reflection: super strong, strongest, strong, medium and weak. For example, the super strong hormone is: 0.05% halometasone (trade name: Xinsuiqiande); the strongest hormone is: 0.05% fluoxymesterone acetate (Botox); the strong hormone is: 0.1% mometasone furoate (Eloson); the medium-effect hormone is: 0.1% hydrocortisone butyrate (Yuzor); the weak-effect hormone is: 0.1% hydrocortisone, etc.
(vii) Topical calcium-adjusted neurophosphatase inhibitors The available ones are tacrolimus (trade name: Putnam) and pimecrolimus (trade name: Anionda). They are safe for topical use, do not cause skin atrophy, no obvious irritation and other adverse reactions, and can be used on the face and skin folds, also for children.
(H) Other topical drugs Pyrithione zinc (trade name: Sigma); new immunomodulators such as Enboc cream, anti-IL-8 (interleukin-8) monoclonal antibody cream; Capsaicin, etc.
Third, the use of topical drugs precautions
Topical drugs are one of the main means of treating psoriasis, and the correct and reasonable use of topical drugs can receive good results. There are many kinds of topical drugs for the treatment of psoriasis, and patients should be reminded to pay attention to them: they must choose the drugs under the guidance of doctors and should not use them arbitrarily. In addition, the following aspects should be noted in the topical application.
1, before applying topical drugs, it is advisable to wash away the scales with warm water first, so that the drugs can better play their role.
2, in the acute stage of psoriasis, when the inflammation of the lesions is obvious, it is not appropriate to use irritating topical drugs, such as anthralin, high concentration of vitamin A acid, etc., so as not to stimulate the occurrence of erythroderma, and the stable stage can use stronger drugs.
3, when the lesions are extensive, the use of topical drugs in a large area can cause poisoning due to excessive absorption. Therefore, the concentration of the selected drug should be reduced, and different drugs should be applied in different areas to reduce the excessive absorption of a single drug. In particular, do not use hormone preparations over a large area.
4, some topical drugs are likely to cause irritation and dermatitis, such as anthralin, Darex, and vincristine, etc. These drugs should be used with special caution on the face and other areas. They cannot be used in areas close to the mucous membranes, such as the perineum, around the anus, etc.
5, axillae, groin and other friction areas and the face are more sensitive to hormones, easily produce skin atrophy, pigmentation, capillary dilation, etc. Therefore, when applying drugs in these areas should use topical hormones with fewer adverse reactions, such as hydrocortisone butyrate ointment (Yuzor), Eloson, etc.. You can also use topical calcium-regulated neurophosphatase inhibitors, such as tacrolimus and pimecrolimus, which can be used in areas where glucocorticoids or retinoids are not suitable for topical use.
6. Infection should be controlled first before treatment. When there is exudation should be treated as acute or subacute dermatitis.
7, the general use of drugs is evenly applied to the affected area and gently pressed softly, twice a day. There are also topical medications that need to be applied only once a day. You should ask your doctor about the specific usage, or refer to the drug’s instruction manual.
8, a doctor had a survey of patients’ knowledge, attitude and behavior of topical medication, the results found that the factors affecting the patient’s compliance with topical medication are mainly the slow efficacy of the drug, the patient can not adhere to the medication, too many varieties, too time-consuming to apply the medication, or a large area of skin lesions, adverse reactions to drugs such as irritation is too large, distrust of physicians, especially when the physician repeatedly invalid prescriptions, bad mood reluctance to use drugs. Therefore, the best way to ensure the correct use of topical medication is to have the correct guidance from the physician on how to use it.