Erythromycin

Type of Medication: Antibiotic

Indications: Treatment of community acquired respiratory infections, atypical infections, Staph. aureus prophylaxis and treatment of staph isolates or minor exacerbations. Possible anti-inflammatory agent. Can be used infrequently as a prokinetic  for constipation

Side Effects: Nausea, vomiting, abdo pain, diarrhoea (antibiotic-associated colitis reported), urticaria, rashes, reversible hearing loss, cholestatic jaundice. Cardiac effects i.e chest pain, arrhythmias. SJS reported and toxic epidermal necrolysis.

Route of administration: Adult (Intravenous)

Dose:500 mg qds or 1 gm bd (CF trust recommends 1g bd)

Administration: Add to 500 ml NaCl 0.9%. Concs upto 5mg/ml may be used, but may be assoc. with pain on infusion.Must be infused over at least 60 minutes. More rapid infusion is more likely to be associated with arrythmias or hypotension.

Route of administration: Adult (Oral)

Dose:500 mg qds or 1 gm bd (CF Trust recommends 1g bd)

Administration: Take with food if nausea is problem, though absorbtion may be reduced. Available as 125mg/5ml, 250 mg/5 ml, 500 mg/5ml and both a 250 and 500 mg tablet or capsule.

Route of administration: Paediatric (Intravenous)

Dose:12.5 mg/kg qds. Can be doubled in severe infection. Max: 1g qds.

Administration:

Route of administration: Paediatric (Oral)

Dose:50mg/kg/day in 2-4 divided doses. Alternatively, <2 years 250mg bd, 2-8 years 500mg bd, >8 years 1g bd.

Examples of some Drug Interactions

Interacting drug: Amiodarone

risk of ventricular arrythmias when administered with intravenous erythromycin.

Interacting drug: Antiepileptics

Increased levels of carbamazepine, phenytoin and sodium valproate.

Interacting drug: Cimetidine

increases erythromycin levels, increases risk of toxicity

Interacting drug: Cisapride

risk of arrythmias – avoid concomitant use

Interacting drug: Cyclosporin

increases cyclosporin level

Interacting drug: Digoxin

may increase digoxin levels (no BNF black spot)

Interacting drug: Itraconazole

may increase itraconazole levels. (No BNF black spot)

Interacting drug: Midazolam

increase plasma midazolam levels with profound sedation.

Interacting drug: Sirolimus

plasma concentration of both drugs increased. Avoid concomitant use.

Interacting drug: Tacrolimus

increases tacrolimus level

Interacting drug: Terfenadine

risk of arrythmias – avoid concomitant use

Interacting drug: Theophylline

increases theophylline level (takes approx 5/7 for interaction)

Interacting drug: Warfarin

increased INR