Use precaution, they have proven to be quite venomous to mice but that really is not proving much because what is potent to mice is not necessarily potent to human beings. There is very little epidemiological information on Buthacus but Algeria lists Buthacus arenicola as medically important and Turkey and Iran lists Buthacus leptochelys (ex B. macrocentrus) as medically important. What is meant by medically important is their venom can produce systemic effects. Not necessarily life-threatening or fatally though. But children, the immunocompromised, and the elderly are a higher risk of greater severe envenomations. Little is known really of Buthacus stings and there is also a great chance that in reality these anecdotal cases are suspected of actually being more potent species namely Buthus, Hottentotta, Leiurus, or Mesobuthus misidentified as Buthacus. Are Buthacus only capable of mild effects or capable of systemic effects? Only their stings are not well documented and the scarce info available is sketchy.
