# 4628
Oseltamivir (Tamiflu) has been approved for use in children over the age of 12 months, but not for younger infants. During the recent pandemic outbreak, an emergency use authorization (EUA) was issued for its use in children under the age of 1 the United States.
The (unproven) concern for giving the drug to children under the age of 1 has been that their supposed immature blood-brain barrier might allow a toxic buildup of the drug in their brains.
This assumption was based in large part on an FDA study back in 2003 where 7-day-old rats were fed a single 1000mg/kg dose of Tamiflu (250 times higher than the recommended dose for children), which resulted in high build ups of the drug in their brains and death.
Details are available in the CMAJ synopsis Oseltamivir (Tamiflu) unsafe in infants under 1 year old.
Of course, rat studies don’t always predict drug behavior in humans.
Today we get a retrospective analysis of the safety and efficacy of Oseltamivir in children under the age of 1 in the Pediatric Infectious Disease Journal.
The researchers evaluated the effects of Tamiflu in 157 infants over five influenza seasons, running from 2003 to 2007. The average age was 6 months, and all infants were given Tamiflu within 48 hours of becoming symptomatic.
Although roughly half experienced complications, most were mild, and generally revolved around nausea, vomiting, and diarrhea.
Follow the link to read the entire paper (Free Access). I’ve excerpted the Abstract below.
doi: 10.1097/INF.0b013e3181cc4d01
Oseltamivir for Treatment of Influenza in Infants Less Than One Year: A Retrospective Analysis
Siedler, Kai MD; Skopnik, Heino MD
Results: In 157 evaluable infants (mean age 6.3 [SD 3.2] months; 86 boys), the most common presenting symptoms other than fever were rhinitis, pharyngitis, cough, feeding difficulties, and otitis media. During treatment, additional symptoms were observed in 78 (50%) infants; most of these were gastrointestinal (vomiting and diarrhea) and of mild intensity.
Fever resolved in 128 (82%) infants within 36 hours of starting oseltamivir (136 [87%] within 48 hours). Complications were recorded in 84 patients (54%), the most serious of which were meningitis in 1 infant (1%), pneumonia in 9 (6%), and otitis media in 2 (1%). Twenty infants received antibiotics for secondary infections (10 [6%] before admission).
Conclusions: The clinical presentation of influenza and outcome of oseltamivir treatment in infants <1 year was similar to that previously reported in older children, but mild gastrointestinal symptoms were common.
As far as the higher rate of gastrointestinal symptoms are concerned, the authors admit that some of these ailments may have been due to factors (rotavirus, norovirus, etc) other than the antiviral being administered.
While small in size and not a Randomized controlled trial (RCT) – these results are encouraging.
