Sulbutiamine sold under the brand names Arcalion, Enerion, and Sulbuxin is a synthetic derivative of thiamine (vitamin B1).

Being a potent cholinergic,[citation needed] sulbutiamine is a popular nootropic, with users reporting enhanced memory, focus, and improved mood and motivation.

[4][5] Adverse effects found in clinical trials are usually limited to headache and gastrointestinal discomfort when high doses are used.

While daily use can result in tolerance and paradoxical drowsiness, increasing the dose is strongly discouraged and side effects can include diarrhea, bladder infections, bronchitis, back pain, abdominal pain, insomnia, constipation, gastroenteritis, headache, vertigo, and sore throat.

[12] In an uncontrollled clinical trial, sulbutiamine was reported to be effective in reducing fatigue in patients with multiple sclerosis.