Oseltamivir
Dosing in kidney impairment
Dosage in Patients with Renal Impairment Table 2 displays the dosage recommendations for the treatment and prophylaxis of influenza in adults with various stages of renal impairment (estimated creatinine clearance of less than or equal to 90 mL per minute). Dosage modifications are recommended in adults with an estimated creatinine clearance less than or equal to 60 mL per minute [see Use in Specific Population and Clinical Pharmacology ] .
Table 2 Recommended Dosage Modifications for Treatment and Prophylaxis of Influenza in Adults with Renal Impairment or End Stage Renal Disease (ESRD) on Dialysis [See table below.] Oseltamivir phosphate for oral suspension is not recommended * Oral suspension can be used for 30 mg dosing. † The recommended duration for post-exposure prophylaxis is at least 10 days and the recommended duration for community outbreak (seasonal/pre-exposure) prophylaxis is up to 6 weeks (or up to 12 weeks in immunocompromised patients). ‡ Data derived from studies in continuous ambulatory peritoneal dialysis (CAPD) patients.
| Renal Impairment (Creatinine Clearance) | Recommended Treatment Regimen* | Recommended Prophylaxis Regimen*† |
| Mild (>60 to 90 mL/minute) | 75 mg twice daily for 5 days | 75 mg once daily |
| Moderate (>30 to 60 mL/minute) | 30 mg twice daily for 5 days | 30 mg once daily |
| Severe (>10 to 30 mL/minute) | 30 mg once daily for 5 days | 30 mg every other day |
| ESRD Patients on Hemodialysis (≤ 10 mL/minute) | 30 mg immediately and then 30 mg after every hemodialysis cycle (treatment duration not to exceed 5 days) | 30 mg immediately and then 30 mg after alternate hemodialysis cycles |
| ESRD Patients on Continuous Ambulatory Peritoneal Dialysis‡ (≤10 mL/minute) | A single 30 mg dose administered immediately | 30 mg immediately and then 30 mg once weekly |
| ESRD Patients not on Dialysis | Oseltamivir phosphate for oral suspension is not recommended | Oseltamivir phosphate for oral suspension is not recommended |
Dosing in liver impairment
Hepatic Impairment No dosage adjustment is required in patients with mild to moderate hepatic impairment. The safety and pharmacokinetics in patients with severe hepatic impairment have not been evaluated [see Clinical Pharmacology ] .
Preparation and administration
Dosage and Administration Overview Administer oseltamivir phosphate for oral suspension for the treatment of influenza in patients 2 weeks of age or older [see Dosage and Administration ] or for prophylaxis of influenza in patients 1 year and older [see Dosage and Administration ] using: Oseltamivir phosphate for oral suspension (supplied as a powder).
This is the preferred formulation (6 mg per mL) for patients who cannot swallow capsules. Prior to use, the supplied oseltamivir phosphate for oral suspension powder must be constituted with water by the pharmacist to produce the oral suspension [see Dosage and Administration ]. The oral suspension may be taken with or without food; however, tolerability may be enhanced if oseltamivir phosphate for oral suspension is taken with food.
Adjust the oseltamivir phosphate for oral suspension dosage in patients with moderate or severe renal impairment [see Dosage and Administration ].
Preparation and Storage of Constituted Oseltamivir Phosphate for Oral Suspension Prior to dispensing to the patient, constitute oseltamivir phosphate for oral suspension (supplied as powder): a) Tap the closed bottle containing the supplied oseltamivir phosphate for oral suspension white to off-white granular powder several times to loosen the powder. b) Measure 55 mL of water in a graduated cylinder. c) Add the total amount of water for constitution to the bottle. d) Close bottle with child-resistant cap tightly and shake the closed bottle well for 15 seconds. e) Label the bottle with instructions to “Shake Well Before Use”. f) The constituted oral suspension contains 360 mg of oseltamivir base per 60 mL of volume (6 mg per mL) and is white to off white color, tutti-frutti flavored homogenous suspension.
Use the constituted oral suspension within 17 days of preparation when stored under refrigeration, 2º to 8ºC (36º to 46ºF), or within 10 days if stored at controlled room temperature, 25ºC (77ºF). Write the expiration date of the constituted oral suspension on the bottle label. g) Ensure patients have an oral dosing dispenser that measures the appropriate volume in milliliters.
Counsel patients on how to utilize the oral dosing dispenser and correctly measure the oral suspension as prescribed (see Tables 1 and 2).
| Weight | Treatment Dosage for 5 days | Prophylaxis Dosage for 10 days* | Volume of Oral Suspension (6 mg/mL) for each Dose† | Number of Bottles of Oral Suspension to Dispense |
| Patients from 2 Weeks to less than 1 Year of Age | ||||
| Any weight | 3 mg/kg twice daily | Not applicable | 0.5 mL/kg§ | 1 bottle |
| Patients 1 to 12 Years of Age Based on Body Weight | ||||
| 15 kg or less | 30 mg twice daily | 30 mg once daily | 5 mL | 1 bottle |
| 15.1 kg to 23 kg | 45 mg twice daily | 45 mg once daily | 7.5 mL | 2 bottles |
| 23.1 kg to 40 kg | 60 mg twice daily | 60 mg once daily | 10 mL | 2 bottles |
| 40.1 kg or more | 75 mg twice daily | 75 mg once daily | 12.5 mL | 3 bottles |