Abstract
Chronic fatigue is a common symptom in people with multiple sclerosis (PwMS) and presents as a reversible motor and cognitive impairment with reduced motivation and a desire to rest. The presentation of fatigue symptomatology in PwMS can be spontaneous or induced by mental or physical activity, temperature and humidity fluctuations, acute infections, and even food ingestion. Even though the exacerbation of fatigue symptomatology due to heat reaction is well established, the role of environmental temperature (ambient temperature and relative humidity) is not yet fully understood, and there is not enough systematic evidence regarding its effect. In this article, we present our opinion (based on the current literature and clinical experience) regarding the role of environmental temperature in the manifestation of fatigue symptomatology in PwMS.