Sulfonamide allergic drug reactions

Adverse effects associated with ocular drugs are not imcommon, bnt serious reactions are extremely rare. These adverse reactions are nsnally manifestations of drug hypersensitivity (allergy) or toxicity. The allergic or toxic reaction usually occurs locally in the ocular tissues. Occasionally, as in erythema multiforme potentiated by sulfonamide agents, adverse reactions can manifest as a systemic response. 

There are many other examples. A study on allergic reactions to sulfa-based dmgs lists 38 sulfonamide nonantibiotic drugs. Based on the rich history of heterocycles in medicine, it is not surprising that sulfonamides dominate to this day. 

All loop diuretics, with the exception of ethacrynic acid, are sulfonamides. Therefore, skin rash, eosinophilia, and less often, interstitial nephritis are occasional adverse effects of these drugs. This toxicity usually resolves rapidly after drug withdrawal. Allergic reactions are much less common with ethacrynic acid. 

Besides -lactams and streptomycin, many other drugs including sulfonamides, and to a lesser extent neomycin, nitrofurans, erythromycin, spiramycin, novobiocin, and the tetracyclines, are known to cause allergic reactions in sensitive persons (80, 91). However, such reactions in humans arc variable and are mostly related to therapeutic use. 

The problems encountered most frequently with sulfonamide drugs include gastrointestinal distress, increased skin sensitivity to ultraviolet light, and allergic reactions. Serious disturbances in the formed blood elements, including blood dyscrasias such as agranulocytosis and hemolytic anemia, may also occur during systemic sulfonamide therapy. 

Numerous systemic drugs have been implicated, including the penicillins and sulfonamides, which can cause swelling of the lids and conjunctiva as part of a generalized urticaria or localized angioneurotic edema. Other drugs implicated in ocular allergic reactions are antidepressants, antipsychotics, antihypertensives, antirheumatics, sedatives, and hypnotics. 

Ocular complications are rare with systemic use of this class of drugs. Lid edema, conjunctivitis, chemosis, anterior uveitis, and scleral reactions have been reported with high-dose administration of sulfenilamide. The observed reactions appear to be analogous to systemic hypersensitivity reactions, such as urticaria and edema, seen in some patients who are allergic to sulfonamides. Several cases of Stevens-Johnson syndrome have been reported in patients of Japanese or Korean descent who were given oral metha-zolamide, a sulfonamide used to decrease lOP. Stevens-Johnson syndrome tends to show acute ocular involvement in 69% of affected individuals.This is stratified into mild ocular involvement in 40%, moderate in 25%, and severe in 4%. Late complications can occin and are usually in the form of severe ocular surfece disease and trichiasis. 

No. These drugs have a sulfonamide structure and cross-sensitivity may precipitate an allergic reaction. 

Type II, or cytolytic, reactions are mediated by both IgG and IgM antibodies and usually are attributed to their ability to activate the complement systerrr The major target tissues for cytolytic reactions are the cells in the circulatory system. Examples of type II allergic responses include penicillin-inhemolytic anemia, methyldopa-indMced autoimmune hemolytic anemia, quinidine-induced thrombocytopenic purpura, and sulfonamide-induced granulocytopenia. These autoimmune reactions to drugs usually subside within several months after removal of the offending agent. 

The antibiotic class of drugs has proliferated immensely since the first clinical use of sulfonamide in 1936 and the mass production of penicillin in 1941. In general, harmful effects have resulted from allergic reactions or inadvertent intravenous overdose. Serious toxicity from a single acute ingestion is rare. Table 11-4 lists common and newer antibacterial agents and their toxicities. 

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