Barley is the first recommendation for hot in-temperament diseases. Barley is soaked in water, which is drunk for coughs and sore throats. The soup made from barley given to anyone suffering from the pain of fever is good.
Prophet (Peace be upon him) recommend barley to cure grief of heart and ailments of the kidney.
Narrated Abu Said Al-Khudri:
In the life-time of Allah’s Apostle , we used to give one Sa’ of food (edible things) as Sadaqat-ul-Fit,r (to the poor). Our food used to be either of barley, raisins (dried grapes), cottage cheese or dates. (Book #25, Hadith #586)