- Discussion:
    - for group A strep (pyogenes), alpha hemolytic strep and n. gonorrhea, s. pneumoniae, mycoplasma, legionnaire's, soft tissue infection with s.aureus;
    - adult: 250-500mg PO qid or 500mg-1gm IV qid;
    - IV administration of erythromycin is painful and may cause thrombophlebitis;
           - this is minimized by giving: 500mg/250-500 ml IV fluid slowly over 6hrs;
    - prophylaxis of bacterial endocarditis: 1gm PO 2hr before procedure; and 0.5gm PO 6hrs later;
    - peds: 20-40 mg/kg/24hr upto max dose of 2 gm/24hr IV or PO in 4 DD;

- Supplied:
    - powder for injection as lactobionate and gluceptate salts 250mg, 500mg, 1gm;
    - base as tablets 250mg, 333mg, 500mg and caps: 125mg, 250mg;
    - estolate as chewable tablets 125mg, 250mg and caps: 125mg, 250mg,
          - estolate salt is associatted with cholestatic jaundice;
          - supplied drops 100 mg/1 ml, susp 125, 250 mg/5 ml, chewable tap 125, 250 mg;
    - suspension 125mg/5ml, 250mg/5ml; stearate as tablets 250mg, 500mg;
    - ethylsuccinate as chewable tablets 200 mg and tabs: 400 mg and suspension 200mg/ml, 400 mg/ml;

- Cautions:
    - beware GI complaints, jaundice;
    - erythromycin base not well absorbed from the GI tract and often used as part of the " condon bowel prep"
         - a 2-3 day prep that includes oral laxatives and cleansing enemas; for an 8 am operation, 1 gm of erythromycin base and 1 gm of neomycin are given at about 1 pm, 3pm, an 11 pm the day prior to surgery;
    - diffusion from blood into CSF minimal even w/ inflammation;
         - ratio of CSF to blood level (%): normal meninges: 1-12, inflammed meninges: 7-25;
    - 15 % of dose will be excreted in urine (w/ nl R F(x))
    - dosing regimens for patients with renal in-sufficiency:
         - dose for 70kg adult (gm/dosing interval in hours):
              - CrCl: > 80, 0.5-1/6
              - CrCl: 50-79, 0.5-1/6
              - CrCl: 30-49, 0.5-1/6
              - CrCl: 10-29, 0.5-1/6
    - otoxicity; requires - dose reductionin hepatic dysfunction;
    - will increase action of benzodiazepines, will increase levels of carbamazepine (nystagmus, N/V ataxia);
    - will increase effectiveness of cortisol, increase serum levels digoxin, will increase serum levels of theophyllin;
    - may cause N/V, seizures, apnea;
    - with oral anticoagulants may increase PT;
    - use lactobionate salt with caution in neonates as it contains benzyl alcohol

Impetigo contagiosa III. Comparative efficacy of oral erythromycin and topical mupirocin.

Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Thursday, December 6, 2012 3:06 pm