Sahih Adab al-Mufrad

Abu Hurairah (may Allah be pleased with him) narrates that a Bedouin came, so the Prophet (peace and blessings be upon him) said: "Has Umm Mildam ever seized you?" He said: What is Umm Mildam? The Prophet (peace and blessings be upon him) said: "It is heat between the skin and the flesh." (i.e., fever). He said: Never. The Prophet (peace and blessings be upon him) said: "Have you ever had a headache (suda‘)?" He said: What is suda‘? The Prophet (peace and blessings be upon him) said: "It is a wind that enters the head and strikes the veins." (i.e., headache). He said: Never. Then when he stood up, the Prophet (peace and blessings be upon him) said: "Whoever wishes to look at a man from the people of Hell, let him look at this one."