In this episode, I’ll discuss parenteral medication considerations for the ketogenic diet.
A high-fat, low-carbohydrate diet may be prescribed to induce ketosis and help patients with epilepsy that is refractory to medical treatment. While dietary carbohydrate intake is tightly controlled in these patients, small amounts of carbohydrate from non-dietary sources such as parenteral medications can shift a patient out of ketosis, potentially precipitating a seizure. To help clinicians prevent this from happening, a group of authors published a review in AJHP of Parenteral medication considerations for the ketogenic diet.
While it is relatively easy to avoid 5% dextrose as a diluent, ingredients such as mannitol, propylene glycol and glycerol are all carbohydrates that have the possibility of shifting a patient out of ketosis. There is no data that has quantified the exact amount of extra carbohydrates from medications that can precipitate seizures. Large enough amounts to shift a patient out of ketosis of mannitol, propylene glycol, and glycerol might be administered in the setting of a continuous infusion.
The authors of the review published in ASHP provide a list of parenteral medications that are known to contain carbohydrates.
For example, CNS parenteral medications that contain carbohydrates include acetaminophen, lorazepam and diazepam, etomidate, pento- and phenobarbital, phenytoin, propofol, and vecuronium. Cardiac parenteral medications that contain carbohydrates include calcium gluconate, digoxin, esmolol, hydralazine, labetalol, nitroglycerin, and some forms of lidocaine. Antimicrobial parenteral medications that contain carbohydrates include sulfamethoxazole/trimethoprim. Many other medications have dextrose as the standard recommended diluent.
The authors recommend the following 3-pronged approach to avoid the risk of inadvertent exposure to carbohydrates from parenteral medications:
(1) institutional protocols to identify and manage patients,
(2) computerized provider order entry order sets in the electronic medical record (EMR) to provide alternatives, and
(3) a multidisciplinary approach to care.
The main purpose of an institutional protocol is to develop awareness and provide education to clinicians about how to care for patients on a ketogenic diet.
In one study changes made to the EMR resulted in half as many orders of medications containing carbohydrates to patients on a ketogenic diet.
As part of a multidisciplinary approach to patient care the authors “recommend consultation with a clinical pharmacist (ideally one trained on the ketogenic diet or specialized in neurology) for both pre- and postoperative medication management to prevent medication errors for patients on the ketogenic diet in acute care settings.”
The review is available for free on ASHP’s site so hospital pharmacists who care for patients on a ketogenic diet can readily access the medication tables and recommendations of the authors.
To access my free download area with 20 different resources to help you in your practice, go to pharmacyjoe.com/free.
If you like this post, check out my book – A Pharmacist’s Guide to Inpatient Medical Emergencies: How to respond to code blue, rapid response calls, and other medical emergencies.
Leave a Reply