Trimethoprim/sulfamethoxazole should not be taken by anyone with a history of sulfa allergy. Many drugs contain sulfur; early examples being antibacterial sulfonamides, known as "sulfa drugs". This was later followed by sulfonamides (sulfa drugs) and penicillin. In the 1930s, antibiotics emerged&colon; first sulfa drugs, then penicillin and other antibiotics. For example, sulfa drugs are sulfonamides derived from aromatic sulfonation. Penicillin and sulfa drugs proved highly successful in this regard. People with a sulfa allergy may also be allergic to bumetanide. People with a sulfa allergy, may also be allergic to bumetanide. The most common manifestations of a hypersensitivity reaction to sulfa drugs are rash and hives. In people with a sulfa allergy certain formulations may result in problems. Chloroquine/proguanil or sulfa drug-pyrimethamine combinations should be used in all other plasmodia infections. Sulfa drugs also act as competitive inhibitors. Azo coupling is also used to produce prontosil and other sulfa drugs. Therefore, because of sulfa drugs' competitive inhibition, they are excellent antibacterial agents. Sulfathiazole is an organosulfur compound used as a short-acting sulfa drug.