CYP3A4 inhibitors - ketoconazole + Retapamulin

Coadministration of ketoconazole increased repamulan  mean AUC and Cmax after topical
application of retapamulan.

Because of low systemic exposure to retapamulin  following local appication, dosage adjustments for retapumulin are not necessary when it is coadministered with CYP3A4  inhibitors  such as ketoconazole

Adverse reactions reported are-

CNS - headache   2%

GI - diarrhea  1%  nausea  1%

Local - application site irritation 1.5%

Miscellaneous-   creatinine phosphate increased  < 1%
  
                             Nasopharyngitis  1%

Warnings-

Local irritation-  in case of severe local irritation, from retapamulin , discontinue usage, wipe off the ointment and institute appropiate therapy

For external use - ratapumulin is not intended for ingestion or for intranasal , opthalmic  or
intravaginal use.

Superinfection - use of antibitics may promote the selection of on- susceptible organisms.
if superinfection occurs, during therapy, take appropiate measures

Pregnancy-  no adequate and well- controlled studies on pregnant women. Use during pregnancy only when the potential benefits outweigh the potential risks

Lactation- safe use of retapamulin during breast feeding has not been established

Children - safety and efficacy of retapamulin in treatment of impetigo have been estabished in children 9mths to 17 years of age. The maginitude of efficacy and safety were similar to those in adults.  Safety and efficacy in children below 9 mths have not been establised

Elderly- no overall differences in safety and eficacy were observed between these and younger adult patients

Indication-

Impetigo  - topical treatment due to Staphylococcus aures

Dosage-

Apply a thin layer of retapamulin  to affected area twice daily for 5 days.
The surface area may be covered  with a sterile bandage or gauze if desired

1. Patients  should use tetapamulin as directed by the doctor. Patients should wash their hands after application if the hands are not the  area of treatment

2. Retapamulin is for external appication only. Instruct patients not to swallow retapamulin , use it in the eyes, on the mouth, or lips, inside the nose, or inside the female genital areas.   

3. The treated area may be covered by a sterile bandage or dressing if required. The bandage will protect the treated area and avoid accidental transfer of ointment to the eyes or other areas.

4. Patients should use the medication for the full course as recommended by the doctor, even though symptoms may have improved

5. Inform patients that retapamulin  may cause reactions at the site of aplication of the ointment. Inform your doctor if the area of application worsens in irritation , redness, itching, burning, swelling,blistering, or oozing occur

Pharmacology-
Retapamulin is an antibacyrtial agent . It is  a semisynthetic derivative of a compound pleuromutilin

Pregnancy- 
No adequate and well- controlled studies on pregnant women. Use during pregnancy
only when the potential benefits outweigh the potential risks

Lactation-
Safety for use of retapamulin during breast feeding has not been established

Children -
Safety and efficacy of retapamulin in treatment of impetigo have been estabished in
children 9mths to 17 years of age. The maginitude of efficacy and safety were similar to those in adults.  Safety and efficacy in children below 9 mths have not been establised

Elderly-
No overall differences in safety and eficacy were observed between these and younger
adult patients