Phenytoin Blood Concentrations in Hospitalized Geriatric Patients: Oral Versus Nasogastric Feeding Tube Administration

Going down the tubes! Impact on seizure control of antiepileptic medication given via percutaneous feeding tubes

BACKGROUND

Long-term feeding by percutaneous endoscopic gastrostomy tube (PEG) is uncommon but can present significant issues when both nutrition and medication have to be fed down the same tube. This is especially important in people with epilepsy where the dose and bioavailability of antiepileptic drugs are critical to maintain adequate seizure control. This group with long-term PEG tubes is particularly vulnerable and dependent on their carers to provide high standard of care. Indeed, approximately half of the people with long-term feeding tubes suffer from severe intellectual disability which requires careful coordination of all members of the multidisciplinary team. It is all the more important when consideration is given that around 50% of people with severe ID have seizures, mostly treatment resistant.

METHOD

A detailed literature review was conducted with the focus on the numerous factors that can affect medication delivery and absorption with the potential to destabilize seizure control in people with PEG. Issues concerning the site of drug absorption, excipients and dilution, interaction between antiepileptic drugs and the nutritional feed, bioavailability, and problems with the PEG tube are considered.

RESULTS

There is limited research in this area and the studies are often based on small numbers, healthy volunteers or in vitro findings.

CONCLUSION

In the absence of sound research data, seizure control in each patient with a PEG needs to be considered on an individual basis. Establishing a baseline by measuring the serum levels prior to the tube insertion may be helpful, followed by checking the levels after PEG insertion.