Drug eruption

Introduction Drug eruption, also known as drug dermatitis, is a reaction of skin mucosal inflammation caused by drugs entering the human body through oral, topical and injection. Almost all drugs may cause dermatitis, but the most common are iodine drugs, antipyretic analgesics, sleeping pills, penicillin, streptomycin, etc. The adverse reactions caused by drugs are very complicated and can be roughly divided into: drugs Excess, intolerance, idiopathic, side effects, secondary effects and allergic reactions. Drug eruptions are the most common type of allergic reaction.

Cause

There are many types of drugs that cause drug eruptions. The common drugs are as follows:

1. Antipyretic analgesics

Among them, pyrazolone and salicylate are the most common.

2. Sulfonamides

Among them, long-acting sulfonamides are more common.

3. Sleeping sedative class

Among them, there are more barbiturates.

4. Antibiotics

Among them, penicillin is common, and other drug eruptions such as furans and phenothiazines are not uncommon.

5. Chinese herbal medicine

In recent years, the reports of drug eruptions caused by Chinese herbal medicines have gradually increased, and the drugs causing allergies have single Chinese herbal medicines and compound preparations.

an examination

Related inspection

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According to the morphology, it can be divided into measles-like or scarlet fever-like rash type, polymorphous erythema type, fixed type, exfoliative dermatitis type, toxic epidermal necrolysis type, urticaria type, vasculitis type, photosensitive type, serum disease type Type, etc., clinically common with rash, fixed, urticaria and polymorphic erythema. Clinical features:

1. A history of useful medicines before the illness, which often occurs suddenly during the course of treatment. The history of medication and the history of previous drug allergy should be asked in detail within 3 weeks before the rash. After stopping the drug, it can heal itself.

2. There is a certain incubation period, the incubation period of the first medication is about 5-20 days, and repeated medication can occur in a few minutes or hours. Anti-gout drugs and anti-tuberculosis drugs have a longer incubation period and can be used for up to 90 days for the first time.

3. Many prodromal symptoms, such as fever, itchy skin, general malaise, etc.

4. May be associated with fever, headache, nausea, fatigue and other systemic symptoms.

5. Severe cases are often accompanied by oral mucosal damage, and may have liver, kidney, heart, joint and hematopoietic damage.

7. The course of the disease is more acute. After the sensitizing drugs are stopped, the mild patients will heal within about 1-3 weeks. The drug or structurally similar drug can be used again.

Differential diagnosis

Symptoms of drug rash

Identification of urticaria-type drug eruption and exfoliative dermatitis-type drug eruption.

Urticaria drug eruption: Most drugs have the possibility of causing drug eruptions, including Chinese herbal medicines, but most of them are caused by more antigenicity. Commonly used antibiotics are penicillin, serum products, terpene, salicylate, sulfonamide, procaine and the like. In addition, for patients with congenital allergic diseases and patients with diseases of vital organs, the risk of drug eruption is relatively high.

Exfoliative dermatitis-type drug eruption is caused by barbiturates, sulfonamides, phenytoin, phenylbutazone, sodium salicylate, penicillin streptomycin and the like. Most cases occur after long-term use. The first incubation period of about 20 days of incubation is based on the drug rash that has been continued. The onset is often accompanied by high fever and chills. At the beginning of the skin lesions, measles-like or scarlet-like fever samples gradually intensify during the development process, and they are integrated into diffuse redness of the whole body. Especially for the face and hands and feet, there may be erosion, herpes or blisters. After the rupture, the exudate clots to about 2 weeks. The whole body skin desquamation is scaly or deciduous, and the hands and feet are peeled off in the form of gloves or socks, and the hair and nails can fall off (healing can be regenerated).

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.