Sulbutiamine is a synthetic derivative of thiamine (Vitamin B1) developed to improve lipid solubility and thereby increase its ability to cross the blood-brain barrier. Thiamine itself has a long-established role in neurological health, with deficiency leading to conditions such as beriberi and Wernicke-Korsakoff syndrome, both of which can involve neuralgia (nerve pain) and neuritis (nerve inflammation). Sulbutiamine has been investigated, primarily in France and Japan, for its effects on fatigue, asthenia, and some neurological symptoms associated with thiamine deficiency.

There is some scientific rationale for using thiamine and its derivatives in neuropathic conditions, as thiamine is essential for nerve function, energy metabolism, and neurotransmission. A few small studies and clinical reports suggest that high-dose thiamine or derivatives like sulbutiamine may reduce symptoms in certain neuropathies, especially those related to diabetes or alcoholism. However, the quality of evidence is generally low, with limited randomized controlled trials specifically addressing neuralgia or neuritis unrelated to deficiency.

While sulbutiamine may be considered as an adjunct in cases where thiamine deficiency is likely, there is insufficient high-quality evidence to support its routine use for neuralgia or neuritis of other causes. Most recommendations are extrapolated from thiamine’s known physiological roles and small clinical studies. Thus, the scientific evidence is limited and rates a 2 out of 5.