Common Side Effects in Children
Omeprazole, a proton pump inhibitor used for acid-related conditions like GERD, causes side effects in children at rates similar to adults but with some pediatric-specific data. In clinical trials for kids aged 1-16 years, about 25-30% experienced any adverse event, though most were mild and not necessarily drug-related.[1][2]
Headache tops the list at 6-7%, followed by abdominal pain (5%), nausea (4%), diarrhea (3%), vomiting (3%), and constipation (2-3%). These occurred in short-term studies (up to 8 weeks) for doses of 5-20 mg daily.[1]
How Side Effects Compare to Placebo
Placebo groups in the same trials reported side effects at comparable rates: headache (5%), abdominal pain (4%), nausea (3%). This suggests omeprazole adds only a small risk increment—roughly 1-3% above background—for most common issues.[1][3]
Serious or Rare Side Effects
Serious events like allergic reactions or severe GI issues are uncommon (<1%). Long-term use (over 12 weeks) links to rare risks such as fractures (0.1-0.5% increased), vitamin B12 deficiency, or infections (e.g., C. difficile), but pediatric data is limited to observational studies showing no strong signals.[2][4] Hypersensitivity occurs in 0.2%.[1]
Differences by Age Group
Infants under 1 year have less trial data; side effects mirror older kids but with higher fussiness or feeding issues (up to 10%, often indistinguishable from disease symptoms). Teens align closely with adult profiles.[2][5]
What Happens with Long-Term Use
Beyond 3 months, monitoring is advised for growth delays (seen in <2% of cases) or hypomagnesemia (<0.1%). Discontinuation rarely causes rebound acid (5-10%).[4]
Factors Raising Risk
Higher doses (>1 mg/kg/day), longer duration, or combo with antibiotics increase GI upset by 2-3x. Kids with liver issues face elevated levels, potentially worsening side effects.[3][5]
[1]: FDA Label - Prilosec (omeprazole)
[2]: PubMed - Safety of PPIs in children (Kaguelidou 2017)
[3]: Cochrane Review - PPIs for GERD in children (van der Pol 2015)
[4]: AAP Guidelines - Pediatric GERD (Rosen 2018)
[5]: DrugPatentWatch - Omeprazole pediatric patents (expired 2014, generics common)