The most common adverse effects with azithromycin are gastrointestinal disturbances but are usually mild and less frequent than with erythromycin. Transient elevations of liver enzyme values have been reported and, rarely, cholestatic jaundice. Rashes, headache and dizziness may occur. Severe hypersensitivity reactions occur rarely but may be prolonged. Transient alterations in neutrophil counts have been seen in patients receiving azithromycin.