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Monograph for inclusion in Handbook Of Drug Administration via Enteral Feeding Tubes (9)
Advance Release (kindly shared with the NHS via NeLM)
OSELTAMIVIR
Formulations Available 1
Brand Name
(Manufacturer)
Tamiflu®
(Roche)
Formulation and Strength
Capsules
30mg,
45mg,
75mg
Product Information / Administration Information
Hard gelatin capsule.
Contents of capsule can be opened and mixed with chocolate syrup, honey, sugar dissolved in water, dessert toppings, sweetened condensed milk, apple sauce or yoghurt (2) .
Contains oseltamivir phosphate.
The contents of the capsule pour easily, but are granular in nature. Once dispersed in water, care must be taken to draw up the entire dose and administer and flush well. Although small particles are visible in the dispersion, this flushes via an 8Fr NG tube without blockage (6) .
For patients with swallowing difficulties or paediatric patients mix the contents of the capsule with one of the food stuffs listed above. For patients where this is not appropriate, correct strength of capsules is not available or the commercial suspension is not available, an extemporaneous product can be produced using the formulation and method detailed at the bottom of this monograph (7) .
Based on pharmaceutical profile of the excipients in the commercial suspension and the suspending agents used above, Diluent A (Nova labs) would be an appropriate alternative (8) .
Tamiflu®
(Roche)
Suspension Contains oseltamivir phosphate.
45mg dose provides 3.6g sorbitol (3) .
Site of absorption (oral administration):
No specific site documented. Absorption is rapid following oral administration (2) , with peak levels occurring between 1 and 4 hours (4,5) .
Alternative routes available:
None available for oseltamivir.
Interactions:
There is no significant interaction between oseltamivir and magnesium, aluminium or calcium containing antacids (2) . Absorption is not affected by food (2) . Absorption is highly unlikely to be affected by enteral feed.
Health and Safety:
Standard precautions apply.

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Total Volume of Compounded Oral
Suspension needed to be Prepared
30 mL
Suggestions / Recommendations:
Disperse capsule contents in water and administer using the method below.
Intragastric Administration
1. Stop enteral feed.
2. Flush enteral feeding tube with the recommended volume of water.
3. Empty the contents of the capsule into a medicine pot.
4. Add 5mL of water and stir to mix thoroughly.
5. Draw the dispersion into an appropriate enteral syringe taking care to draw up all particles.
6. Flush this via the feeding tube.
7. Add another 5mL of water to the medicine pot, stir and draw into the syringe. This will ensure no residual dose remains in the pot.
8. Flush this via the feeding tube.
9. Finally, flush with the recommended volume of water.
10. Re-start the feed, unless a prolonged break is required.
Intrajejunal Administration
No specific data relating to jejunal administration of oseltamivir. Administer using the above method.
Extemporaneous Preparation
See notes above regarding alternative suspending agents.
This compounding procedure results in a 15 mg/mL suspension, which is different from the commercially available TAMIFLU for Oral Suspension, which has a concentration of 12 mg/mL.
40 mL 50 mL 60 mL
Required number of TAMIFLU 75 mg
Capsules
6 capsules
(450 mg oseltamivir)
8 capsules
(600 mg oseltamivir)
10 capsules
(750 mg oseltamivir)
12 capsules (900 mg oseltamivir)
Required volume of vehicle
Cherry Syrup (Humco) OR
Ora-Sweet SF (Paddock Labs)
29 mL 38.5 mL 48 mL 57 mL
1. Carefully separate the capsule body and cap and transfer the contents of the required number of TAMIFLU
75 mg Capsules into a clean mortar.
2. Grind the granules to a fine powder.
3. Add one-third (1/3) of the specified amount of vehicle and mix with the powder until a uniform suspension is achieved.
4. Transfer the suspension to an amber glass or amber polyethyleneterephthalate (PET) bottle.
5. Add another one-third (1/3) of the vehicle to the mortar, mix with any remaining residue in the mortar and transfer the vehicle into the bottle.
6. Repeat the rinsing (Step 5) with the remainder of the vehicle.
7. Close the bottle using a child-resistant cap.
8. Shake well to completely dissolve the active drug and to ensure homogeneous distribution of the dissolved drug in the resulting suspension. (Note: The active drug, oseltamivir phosphate, readily dissolves in the specified vehicles. The suspension is caused by some of the inert ingredients of TAMIFLU Capsules which are insoluble in these vehicles.)
9. Put an ancillary label on the bottle indicating “Shake Gently Before Use”. [This compounded suspension should be gently shaken prior to administration to minimize the tendency for air entrapment, particularly with the Ora-Sweet SF preparation.]
10.Instruct the parent or guardian that any remaining material following completion of therapy must be discarded.

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11.Place an appropriate expiration date label according to storage condition (see below).
STORAGE:
Refrigeration:
Stable for 5 weeks (35 days) when stored in a refrigerator at 2° to 8°C (36° to 46°F).
Room Temperature: Stable fo r five days (5 days) when stored at room temperature, 25°C (77°F).
Note: The storage conditions are based on stability studies of compounded oral suspensions, using the above mentioned vehicles, which were placed in amber glass and amber polyethyleneterephthalate (PET) bottles.
Stability studies have not been conducted with other vehicles or bottle types.
Dosing Chart for Pharmacy-Compounded Suspension from TAMIFLU Capsules 75 mg
Body Weight
(kg)
Body Weight
(lbs)
Treatment Dose (for 5 days)
Prophylaxis Dose
(for 10 days)
≤15 kg
16 to 23 kg
24 to 40 kg
≥41 kg
≤33 lbs
34 to 51 lbs
52 to 88 lbs
≥89 lbs
Dose
(mg)
Volume per
Dose
15 mg/mL
30 mg 2 mL
45 mg 3 mL
60 mg 4 mL
75 mg 5 mL
2 mL two times a day
3 mL two times a day
4 mL two times a day
5 mL two times a day
2 mL once daily
3 mL once daily
4 mL once daily
5 mL once daily
The dosing device dispensed with the commercially available TAMIFLU for Oral Suspension should NOT be used with the compounded suspension since they have different concentrations.
References:
1. BNF 55, March 2008
2. Tamiflu 75mg Capsule (Roche), Summary of Product Characteristics, 26 January 2009.
3. Tamiflu 12mg/ml powder for oral suspension (Roche), Summary of Product Characteristics, 26
January 2009.
4. M.Abe et al (2006) Pharmacokinetics of Oseltamivir in young and very old subjects. The
Annals of Pharmacotherapy. 40;1724-30.
5. R.Robson et al (2006) The pharmacokinetics and tolerability of oseltamivir suspension in patients on haemodialysis and continuous ambulatory peritoneal dialysis. Nephrol Dial
Transplant 21;2556-2562.
6. BPNG data on file (2009)
7. Winiarski.A.P. et al (2007) Preparation and stability of extemporaneous oral liquid formulations of oseltamivir using commercially available capsules. J Am Pharm Assoc 47(6):747-55.
8. Personal communication Nova Labs, 1 st May 2009.
9. White & Bradnam (2007) Handbook of Drug Administration via Enteral Feeding Tubes.
PharmPress ISBN 8-85369-648-9
Written by: Rebecca White, Editor Handbook of Drug Administration via Enteral Feeding Tubes
Checked by: Victoria Mott, Lead Medicines Information Pharmacist, Oxford Radcliffe Hospitals NHS Trust
May 2009
Please direct any comments on this monograph to rebecca.white@orh.nhs.uk