Dosage interval

Several adaptive mechanisms by the kidney limit effectiveness of loop diuretic therapy. Postdiuretic sodium retention occurs as the concentration of diuretic in the loop of Henle decreases. This effect can be minimized by decreasing the dosage interval (i.e., dosing more frequently) or by administering a continuous infusion. Continuous infusion loop diuretics may be easier to titrate than bolus dosing, requires less nursing administration time, and may lead to fewer adverse reactions. 

Use of nasolacrimal occlusion will increase number of patients successfully treated with longer dosage intervals. 

Sampling Interval To be able to perform valid toxicokinetic analysis, it is not only necessary to properly collect samples of appropriate biological fluids, but also to collect a sufficient number of samples at the current intervals. Both of these variables are determined by the nature of the answers sought. Useful parameters in toxico-kinetic studies are Cmax, which is the peak plasma test compound concentration Tmax, which is the time at which the peak plasma test compound concentration occurs, Cmin, which is the plasma test compound concentration immediately before the next dose is administered AUC, which is the area under the plasma test compound concentration-time curve during a dosage interval, and t which is the half-life for the decline of test compound concentrations in plasma. The samples required to obtain these parameters are shown in Table 18.12. Cmin requires one blood sample immediately before a dose is given and provides information on accumulation. If there is no accumulation in plasma, the test compound may not be detected in this sample. 

Creatinine clearance (mL/min) Loading dose (mg) Dose (mg) Dosage interval (h)... 

Renai function impairment Because the drug is excreted principally via the kidney, increase the dosage interval in patients with impaired renal function. 

In patients undergoing continuous ambulatory peritoneal dialysis, administer cefepime at normal recommended doses at a dosage interval of every 48 hours. 

Renal function impairment- Use usual dose and schedule in patients with Ccr levels at least 50 mL/min. Patients with Ccr between 10 and 49 mL/min may be given half the recommended dose at the usual dosage interval. Patients with Ccr levels less than 10 mL/min may receive recommended dose given every 3 to 5 days patients on hemodialysis should receive another dose following dialysis. 

Normal dosage at prolonged intervals If the Ccr is not available and the patient s condition is stable, calculate a dosage interval (in hours) for the normal dose by multiplying the patient s serum creatinine by 9. 

Renal fa/Vwre - Calculate the dosage interval with the following formula Serum creatinine (mg/dL) x 9 equals dosage interval (in hours). 

Bisphosphonates such as etidronate are often coprescribed with calcium supplements in the treatment of osteoporosis. If these are ingested concomitantly, the bioavailability of both is significantly reduced with the possibility of therapeutic failure. This may be avoided by allowing a sufficiently long dosage interval a possible approach is to give etidronate for 2 weeks and calcium supplements for 10 weeks in a 12-week period. 

Procainamide is an effective antiarrhythmic agent when given in sufficient doses at relatively short (3-4 hours) dosage intervals. Procainamide is useful in the treatment of premature atrial contractions, paroxysmal atrial tachycardia, and atrial fibrillation of recent onset. Procainamide is only moderately effective in converting atrial flutter or chronic atrial fibrillation to sinus rhythm, although it has... 

Creatinine Clearance Dosage Percent Dosage Interval... 

Dosaye in renal impairment Dosage interval is modified based on creatinine clearance. Creatinine clearance 10-30ml/min.Usualdoseql2h. Creatinine clearance less than 10 ml/min. Usual dose q24h. 

Dosage in renal impairment Dosage interval is modified based on creatinine clearance. 

Dosage in renal impairment Creatinine clearance greater than 41-60 mVmin. Dosage interval q 12h Creatinine clearance 20-40 ml/min. Dosage interval q24h. Creatinine clearance... 

Offers no significant advantage over tetracycline shares similar spectrum of activity (may be slightly less active than tetracycline and has longer dosage interval)... 

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