Convulsive seizures, peripheral neuropathy. GI disturbances particularly nausea, headache, anorexia, vomiting, diarrhea, epigastric distress, abdominal cramping. Sharp unpleasant metallic taste; furry tongue, glossitis, stomatitis; reversible neutropenia, T-wave flattening (ECG tracings); dizziness, vertigo, incoordination, ataxia, confusion, irritability, depression, weakness, insomnia; urticaria, erythematous rash, flushing, nasal congestion, dryness of mouth (or of vag/vulva), fever; dysuria, cystitis, polyuria, incontinence, sense of pelvic pressure; candida proliferation in vag, dyspareunia, decreased libido, proctitis, fleeting joint, faints (serum sickness-like).