Renal disease alters the effects of many drugs, particularly when active drug moieties are renally cleared.

1. PRESENT ED B Y: D R. K A PI L RA ST O GI
DRUG DOSING IN
RENAL FAILURE

2. DOSE V/S DOSAGE
 DOSE: it refers to a specified amount of medication
taken at one time.
 DOSAGE: it refers to the prescribed administration
of a specific amount , number, and frequency of
doses over a specific period of time.

3. RENAL DISEASE: EFFECTS
 Patients are more vulnerable to given drug.
 Drug effect may increase or decrease.
 Higher steady state concentration when given in
usual doses.

4. ASSESMENT OF RENAL FUNCTION
 SERUM CREATININE: Creatinine is waste product
when you move your muscle.
 Healthy kidney removes creatinine from the blood.
 Normal range: 0.6- 1.1 mg/dl {male}
 0.7- 1.3 mg/dl {female}

5. BUN: It measures waste{ urea} in blood
Body makes urea when it breaks down protein
Normal range: 10- 20 mg/dl
It increases GI bleed , heart failure, drug

6. ESTIMATING RENAL FUNCTIONS
 Serum creatinine: inverse relations with renal
function.
 Renal function decreases with age.
 Renal function has linear relationship with lean body
mass.
 Women’s s. creatinine is 0.85 of renal function of
man’s

7. CREATININE CLEARANCE
 It compares creatinine in serum and urine.
 Normal range: 88-128 ml/min {female}
 97-137 ml/min {male}
 Cockcroft Gault formula:
 CR CL= {140-AGE} lean body weight{kg} 0.85
{female}/ 72{serum creatinine}

8. LIMITATIONS
 Higher drug dosing
 Overestimates renal function
 Narrow therapeutic index drugs less reliable
 Unreliable in extremes of body size

9. eGFR
 It measures adjusted GFR taking average body size
in consideration.

10. Prescribing for DIALYSIS patient
 If a drug is known to be dialysed may be given after
the dialysis.

11. DRUG DOSING
 Loading dose: it does not change because it
depends on Vd{ volume distribution}.
 Maintenance dose: it depends on clearance of the
drug.
 Dose reduction
 Dosing interval increased

12. DRUGS THAT DO NOT REQUIRE RENAL
ADJUSTMENTS
 Moxifloxacin Linezolid
 Azithromycin Tigecyclin
 Ceftriaxone Ambisome
 Clindamycin Voriconazole
 Metrogyl Clavulate
 Doxicyclin

13. RENAL DOSING
 For renal dosing pharmacokinetics is most
important.
 How the body affects the drug.

14. LASIX IN RENAL FAILURE
 Lasixs is contraindicated in patient with anuria.
 Used cautiously in patient with renal disease,
precipitates azotemia.

15. DRINKS FOR KIDNEY DISEASE
 WINE
 Cranberry juice
 Lemon
 water

16. ADJUSTING DOSING INTERVAL
 Vancomycin
 Teichoplanin
 Frequent dosing will only increase toxicity not
efficacy.
 Concentration dependent killers
 ADJUST DOSE: time dependent killers{ FQ}

17. Why does’nt it matters for some
antibiotics
 Risk of toxicity is low
 Patient can tolerate higher concentration
 Eg: beta-lactams , carbapenam

18. Antibiotics significantly depending on renal
excretion
 Carbapenams
 Vancomycin
 Acyclovir
 Fluconazole
 Beta – lactams
 Cephalosporins except ceftriaxone

19. ATT IN RENAL FAILURE
 ETHAMBUTOL avoid
 Used cautiously: Streptomycin
 Amikacin
 Capreomycin
 cycloserine
 PAS
Hd leads to elimination of most TB drugs. So ATT
given after dialysis.

20. THANK YOU