Dicloxacillin dosing

For oral therapy, cloxaciUin and dicloxacillin are comparable alternatives. Both undergo hepatic metabolism, and neither drug requires dose adjustment in patients with hepatic insufficiency. Additional pharmacokinetic data are in Table 45.1. Indications for cloxacillin or dicloxacillin include clinically mild staphylococcal infections like impetigo. 

Nafcillin is primarily cleared by biliary excretion. Oxacillin, dicloxacillin, and cloxacillin are eliminated by both the kidney and biliary excretion no dosage adjustment is required for these drugs in renal failure. Because clearance of penicillins is less efficient in the newborn, doses adjusted for weight alone result in higher systemic concentrations for longer periods than in the adult. 

Dicloxacillin 25-50 m kg in tour divided doses Cephalexin 25-50 m kg in tour divided doses Clindamycin 10-30 m k day in three to tout divided doses"... 

Dicloxacillin 25-50 m kg in four divided doses + penicillin VK 40,000-90,000 unhVkg in four divided doses... 

A patient experienced the effects of interactions of warfarin with nafcillin and dicloxacillin (333). During co-administration of nafcillin, warfarin doses were increased to as much as 4.5 times the previous amounts needed to provide adequate anticoagulation. During co-administration of dicloxacillin, warfarin doses gradually fell, but still stabilized at a higher maintenance dose than before. 

Benzylpenicillin is a p-lactam with low or no renal toxicity [21]. However, when administered in large doses, benzylpenicillin or amoxicillin [22] have the potential to induced nephrotoxicity. Acute interstitial nephritis and disturbances of blood electrolytes have also been reported [23]. By comparison, dicloxacillin induced a pathological increase of creatinine, while cloaxicillin had only a marginal effect on the renal function [24]. 

Nafcillin is primarily cleared by biliary excretion while dicloxacillin is eliminated by both kidney and biliary excretion. No dose adjustments are needed in the setting of renal or hepatic dysfunction. 

Since staphylococcal and streptococcal cellulitis are indistinguishable clinically," administration of a semisynthetic penicillin (nafcillin or oxacillin) is recommended until a definitive diagnosis, by skin or blood cultures, can be made " " (Table 108-3). Mild to moderate infections not associated with systemic symptoms may be treated orally with dicloxacillin. If documented to be a mild cellulitis secondary to streptococci, oral penicillin VK or intramuscular procaine penicillin may be administered. More severe infections, either staphylococcal or streptococcal, should be treated initially with intravenous antibiotic regimens. Ceftriaxone 50-100 mg/kg as a single daily dose is efficacious in the treatment of celluMs in pediatric patients. The usual duration of therapy for cellulitis is 7 to 10 days. " ... 

For infections developing more than 36 to 48 hours after the bite, the risk of P. multocida being involved decreases dramatically. In these patients, staphylococci or streptococci are the most likely causative pathogens. Therapy in this instance includes a penicillinase-resistant penicillin (dicloxacillin 250-500 mg orally four times daily in children, 25-50 mg/kg per day oraUy divided into four doses) or a cephalosporin (cefuroxime axetil 500 mg orally twice daily in children, 20-30 mg/kg per day orally divided into two doses) and should be given for a full 10 to 14 days. ... 

A study in 18 healthy subjects found that rifampicin 600 mg daily for 10 days decreased the maximum plasma level of a single 1-g dose of dicloxacillin by 27% and increased the mean oral clearance by 26%. The mean absorption time increased from 0.71 to 1.34 hours. Rifampicin increased the formation clearance, maximum level and AUC of the 5-hy-droxymetabolite of dicloxacillin by 135%, 119%, and 59%, respectively. Dicloxacillin is a substrate of P-glycoprotein and it was suggest that the... 

The reduced effect of warfarin with dicloxacillin and nafcillin appears to be established. If these penicillins are used, increase monitoring of the INR and anticipate the need to increase the warfarin dose. Some patients taking nafcillin have been warfarin resistant, and needed heparin treatment. 

An 80-year-old patient with advanced thyroid cancer taking levothyroxine 125 micrograms daily required treatment with oral ciprofloxacin 750 mg twice daily and intravenous dicloxacillin for osteomyelitis complicating a fracture. After 4 weeks of treatment she complained of increasing tiredness, and was found to have a markedly raised TSH level (10 times of the upper limit of normal). Increasing the levothyroxine dose to 200 micrograms daily did not have any effect on TSH, so the dose was returned to 125 micrograms. The ciprofloxacin was then stopped, and the thyroid function tests rapidly normalised. ... 

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