In clinical studies involving 1,118 patients, the following adverse effects were considered to be related to cinoxacin therapy:
Gastrointestinal: Nausea was reported most commonly and occurred in less than 3 in 100 patients. Other side effects, occurring less frequently (1 in 100), were anorexia, vomiting, abdominal cramps/pain, perverse taste, and diarrhea.
Central Nervous System: The most frequent side effects were headache and dizziness, reported by 1 in 100 patients. Other adverse reactions possibly related to Cinobac (cinoxacin) include insomnia, drowsiness, tingling sensation, perineal burning, photophobia, and tinnitus. These were reported by less than 1 in 100 patients.
Hypersensitivity: Rash, urticaria, pruritus, edema, angioedema, and eosinophilia were reported by less than 3 in 100 patients. Rare cases of anaphylactic reactions have been reported. Toxic epidermal necrolysis has been reported very rarely. Erythema multiforme and Stevens-Johnson syndrome have been reported with cinoxacin and other drugs in this class.
Hematologic: Rare reports of thrombocytopenia.
Laboratory values reported to be abnormal were, in descending order of frequency, elevation of BUN (1 in 100), AST (SGOT), ALT (SGPT), serum creatinine, and alkaline phosphatase; and reduction in hematocrit/hemoglobin (each less than 1 in 100).
Although not observed in the 1,118 patients treated with cinoxacin the following side effects have been reported for other drugs in the same pharmacologically active and chemically related class: restlessness nervousness, change in color perception, difficulty in focusing, decrease in visual acuity, double vision, weakness, constipation, erythema and bullae feelings of disorientation or agitation or acute anxiety, palpitation, soreness of the gums, joint stiffness, swelling of the extremities, and toxic psychosis or convulsions (rare). All adverse reactions observed with drugs in this class were reversible.
The most frequently reported adverse events in post marketing surveillance of cinoxacin have been rash and anaphylactic reactions. Other frequently reported reactions have been pruritus, urticaria, allergic reactions, nausea, abdominal pain, and headache.