As with erythromycin and other macrolides, rare serious allergic reactions, including angioedema and anaphylaxis (rarely fatal), have been reported. Some of these reactions with azithromycin have resulted in recurrent symptoms and required a longer period of observation and treatment.
Since liver is the principal route of elimination for azithromycin, the use of azithromycin should be undertaken with caution in patients with significant hepatic disease.
In patients receiving ergot derivatives, ergotism has been precipitated by coadministration of some macrolide antibiotics. There are no data concerning the possibility of an interaction between ergot and azithromycin. However, because of the theoretical possibility of ergotism, azithromycin and ergot derivatives should not be coadministered.
As with any antibiotic preparation, observation for signs of superinfection with non-susceptible organisms, including fungi is recommended.
In patients with severe renal impairment (glomerular filtration rate <10 ml/min) a 33% increase in systemic exposure to azithromycin was observed.
QT Prolongation: Prolonged cardiac repolarization and QT interval, imparting a risk of developing cardiac arrhythmia and torsades de pointes, have been seen in treatment with macrolides, including azithromycin. Cases of torsades de pointes have been spontaneously reported during post-marketing surveillance in patients receiving azithromycin. Providers should consider the risk of QT prolongation which can be fatal when weighing the risks and benefits of azithromycin for at-risk groups including: Patients with known prolongation of the QT interval, a history of torsades de pointes, congenital long QT syndrome, bradyarrhythmias or uncompensated heart failure; Patients on drugs known to prolong the QT interval; Patients with ongoing proarrhythmic conditions such as uncorrected hypokalemia or hypomagnesemia, clinically significant bradycardia, and in patients receiving Class IA (quinidine, procainamide) or Class III (dofetilide, amiodarone, sotalol) antiarrhythmic agents; Elderly patients may be more susceptible to drug-associated effects on the QT interval.
In the event of severe acute hypersensitivity reactions, such as anaphylaxis, severe cutaneous adverse reactions (SCARs) [e.g. Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS) and acute generalised exanthematous pustulosis (AGEP)], Azicine should be discontinued immediately and appropriate treatment should be urgently initiated.
Effects on ability to drive and use machines: There is no evidence to suggest that azithromycin may have effect on the patient's ability to drive or operate machinery.
Use in Children: Infantile
hypertrophic pyloric stenosis (IHPS) has been reported following the
use of azithromycin in infants (treatment up to 42 days of life).
Parents and caregivers should be informed to contact their physician if
vomiting and/or irritability with feeding occurs.