Neggram Side Effects, and Drug Interactions - Nalidixic Acid

Neggram Side Effects, and Drug Interactions - Nalidixic Acid

SIDE EFFECTS

Reactions reported after oral administration of NegGram include the following.

CNS effects:   drowsiness, weakness, headache, and dizziness and vertigo. Reversible subjective visual disturbances without objective findings have occurred infrequently (generally with each dose during the first few days of treatment). These reactions include overbrightness of lights, change in color perception, difficulty in focusing, decrease in visual acuity, and double vision. They usually disappeared promptly when dosage was reduced or therapy was discontinued. Toxic psychosis or brief convulsions have been reported rarely, usually following excessive doses. In general, the convulsions have occurred in patients with predisposing factors such as epilepsy or cerebral arteriosclerosis. In infants and children receiving therapeutic doses of NegGram, increased intracranial pressure with bulging anterior fontanel, papilledema, and headache has occasionally been observed. A few cases of 6th cranial nerve palsy have been reported. Although the mechanisms of these reactions are unknown, the signs and symptoms usually disappeared rapidly with no sequelae when treatment was discontinued.

Gastrointestinal:   abdominal pain, nausea, vomiting, and diarrhea.

Allergic:   rash, pruritus, urticaria, angioedema, eosinophilia, arthralgia with joint stiffness and swelling, and anaphylactoid reaction. Erythema Multiforme and Stevens-Johnson syndrome have been reported with nalidixic acid and other drugs in this class. Rash was the most frequently reported adverse reaction. Photosensitivity reactions consisting of erythema and bullae on exposed skin surfaces usually resolve completely in 2 weeks to 2 months after NegGram is discontinued; however, bullae may continue to appear with successive exposures to sunlight or with mild skin trauma for up to 3 months after discontinuation of drug. (See PRECAUTIONS.)

Other:   rarely, cholestasis, paresthesia, metabolic acidosis, thrombocytopenia, leukopenia, or hemolytic anemia, sometimes associated with glucose 6-phosphate dehydrogenase deficiency.

Elevated plasma levels of theophylline have been reported with concomitant quinolone use. There have been reports of theophylline-related side effects in patients on concomitant therapy with quinolones and theophylline. Therefore, monitoring of theophylline plasma levels should be considered and dosage of theophylline adjusted, as required.

Quinolones have been shown to interfere with the metabolism of caffeine. This may lead to reduced clearance of caffeine and the prolongation of its plasma half-life.

Quinolones, including nalidixic acid, may enhance the effects of the oral anticoagulant warfarin or its derivatives. When these products are administered concomitantly, prothrombin time or other suitable coagulation test should be closely monitored.

Nitrofurantoin interferes with the therapeutic action of nalidixic acid.

Antacids containing magnesium, aluminum, or calcium; sucralfate or divalent or trivalent cations such as iron; multivitamins containing zinc; and Videx®, (Didanosine), chewable/buffered tablets or the pediatric powder for oral solution may substantially interfere with the absorption of quinolones, resulting in systemic levels considerably lower than desired. These agents should not be taken within the two hour period before or within the two-hour period after nalidixic acid administration.

Elevated serum levels of cyclosporine have been reported with the concomitant use of some quinolones and cyclosporine. Therefore, cyclosporine serum levels should be monitored and appropriate cyclosporine dosage adjustments made when these drugs are used concomitantly.