A NEW review details ketogenic diet contraindications, adverse effects, and drug interactions across routine clinical contexts now.
Ketogenic Diet Contraindications
The ketogenic diet was originally developed for neurological disorders but has drawn increasing attention for potential roles in metabolic disease management. As clinical use has expanded, the authors of a 2026 narrative review examined where ketogenic dietary patterns may be unsuitable, where extra caution is commonly discussed, and which medication interactions may be clinically relevant.
Within the paper, the authors describe rare absolute contraindications. These include selected inborn errors of metabolism involving pyruvate carboxylase activity, carnitine transport or utilization, and fatty acid oxidation pathways, as well as porphyria. The review also outlines relative contraindications that may be complicated by ketogenic diet related metabolic changes, including acute pancreatitis, advanced hepatic disease, advanced renal disease, and familial hypercholesterolemia. The paper also notes circumstances where propofol use is considered relevant in relation to ketogenic diet related risk.
Drug Interactions and Reported Side Effects
A major focus of the review is potential drug interactions in people following ketogenic dietary patterns, particularly in those with diabetes and other cardiometabolic comorbidities. The authors discuss interactions involving glucose lowering therapies, including sodium glucose cotransporter 2 inhibitors, metformin, glucagon like peptide 1 receptor agonists, insulin, and sulphonylurea derivatives. They also review considerations involving antiepileptic drugs, diuretics, lipophilic drugs, and corticosteroids.
Across the review, additional clinical situations are described as warranting particular caution, including pharmacologically treated hypertension, gallbladder disease or prior cholecystectomy, electrolyte disturbances, cardiac arrhythmias, pregnancy or lactation, underweight status, intense physical activity, significant psychosocial stress, and postoperative recovery.
The most frequently reported adverse effects summarized in the paper range from transient “keto flu” symptoms such as fatigue, headache, and nausea to gastrointestinal disturbances, polyuria, and hypoglycemia. Overall, the authors frame ketogenic diet contraindications and medication interactions as central safety considerations alongside tolerability, particularly as ketogenic approaches are applied across varied metabolic and neurological contexts.
Reference: Dyńka D et al. The ketogenic diet is not for everyone: contraindications, side effects, and drug interactions. Ann Med. 2026;58(1):2603016.
