The need for long-term thromboprophylaxis in children using warfarin therapy is increasing. Natural health products (NHPs) are administered to children by parents who perceive them to be useful and acceptable adjuncts or alternatives to conventional therapies. Interactions of NHPs with prescribed therapies may result in serious adverse events. NHP usage is underevaluated in children and there are no studies evaluating NHP usage in warfarinized children.
Objectives:
To explore NHP use in warfarinized children and their siblings to determine the prevalence, varieties, and reasons for NHP usage, as well as the potential effect on warfarinization (eg, time in therapeutic range [TTR]).
Methods:
This is a 3-phase cross-sectional cohort study that includes the (1) prevalence (2) NHP education and knowledge assessment, and (3) the follow-up NHP utilization phase.
Results:
Forty-six percent of warfarinized children consumed NHPs, with time in therapeutic range of 74%. The mean score for baseline knowledge of NHPs and warfarin following the education phase was 67%. Follow-up NHP use was 30%, and increased consistency of utilization with TTR was 83% (p < 0.05), consistent with education provided.
Conclusions:
The consistent prevalence rates over time of NHP usage in warfarinized children indicate the need for future studies. Education remains vital to combat the potential risks of NHP-warfarin interaction, encouraging patient disclosure and consistency.
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