Drug rashes are skin irritations that occur due to allergic reactions to medications or antibiotics. They look like small bumps, or scaly itchy skin patches. The appearance of these rashes vary in both appearance and severity. Amoxicillin is one antibiotic some people have difficulty tolerating. If you are allergic to one antibiotic, be sure to tell your doctor or dentist as they may want to prescribe you a medication in that same class unless they know you have a skin reaction to it.

People react to different drugs at different times. Sometimes only takes the first usage to get a reaction, while others take multiple dosages. Drug rashes can be a known side effect of certain medications. If you are taking medications like iodine and steroids, you may exhibit rashes that look like acne and red spots. This rash usually appears on the shoulders, face, and chest. Rashes caused by antibiotic use appear as scaly red skin or a purplish rash. Barbituate use tends to cause red rashes that look like measles, while blood thinners cause skin eruptions on the legs. Hives eruptions can appear those who are allergic to aspirin.

Urticaria skin rash can also occur from various drugs for many health conditions for others. After taking omnicef last year, I broke out in a rash that looked like eczema, but it may have been the strep infection itself and not the medication as strep rashes can also occur. Maculopapular rashes are bumps on a red flat area and can be a reaction to antibiotics such as amoixcillin or chemotherapy medications used to treat cancer.
 
A very serious reaction to medication and antibiotics like penicillin can cause Steven Johnson Syndrome. This condition causes blister and hives to form on the mucous membranes located in the eyes and mouth. Often hospitalization is necessary for this condition. Erytheme multiforme minor can also occur first and develop into SJ Syndrome. Thalidomide, is a medication that is use for certain cancers. It is prescribed under the intense supervision of a doctor. This drug causes many side effects. Some of the side effects are topical skin rashes and acne, fungal skin inflammation, psoriasis, hives, and herpes simplex. Anti-depressant medications can also cause rash eruptions and though not common, a side effect such as a lamictal rash on the arms can occur for some people.
 
The drug rashes that are mild and non-threatening can be treated with cold compresses and showers. The rashes that are itchy, can be relieved by applying calamine lotion or the use of antihistamines. Small scale rashes can be treated topically while rashes that cover large areas of the body get treated by injection or orally.