Can Tamiflu 45 mg Capsules Be Opened?
Yes, Tamiflu (oseltamivir) 45 mg capsules can be opened and the contents mixed with liquid for administration, particularly when patients cannot swallow capsules whole. 1
Administration Methods for Capsule Contents
The American Academy of Pediatrics explicitly recommends that oseltamivir capsules can be opened and mixed with liquid, with a preferred final concentration of 6 mg/mL when compounding is needed. 1 This guidance applies to all capsule strengths, including the 45 mg formulation.
Mixing Instructions
- Mix capsule contents with simple syrup or Ora-Sweet SF to achieve a final concentration of 6 mg/mL if preparing an extemporaneous suspension. 1
- The commercially manufactured oral suspension (6 mg/mL) remains the preferred formulation when available, but opening capsules is an acceptable alternative. 1
- If the commercial suspension is unavailable, retail pharmacies can compound a suspension based on package label instructions. 1
Clinical Context for Opening Capsules
This practice is particularly useful in several scenarios:
- Pediatric patients who cannot swallow capsules whole and require weight-based dosing (the 45 mg dose corresponds to children weighing >15-23 kg or >33-51 lb). 1
- Patients with dysphagia or other swallowing difficulties who need the medication but cannot take solid dosage forms. 1
- Situations where liquid formulation is temporarily unavailable and capsule contents must be used to prepare an alternative. 1
Important Administration Considerations
- Taking oseltamivir with food significantly reduces gastrointestinal side effects (nausea and vomiting), which occur in approximately 10% of patients. 1, 2
- The medication should be initiated within 48 hours of symptom onset for maximum effectiveness, regardless of formulation used. 1, 3
- When opening capsules, ensure accurate dosing by using proper measuring devices, as the 45 mg dose equals 7.5 mL of the standard 6 mg/mL suspension. 1
Common Pitfall to Avoid
Do not assume that opening capsules compromises drug efficacy—the active ingredient (oseltamivir phosphate) is stable when mixed with appropriate vehicles and maintains its bioavailability. 1 The prodrug is converted to the active metabolite (oseltamivir carboxylate) in the liver after absorption, regardless of whether it was administered as an intact capsule or mixed contents. 4