Hi, My Son Is Currently Confine In The Hospital Due

Hi, my son is currently confine in the hospital due to typhoid and acute bronchitis. He is sick for almost a week. My worry is that he cough very bad and blow up with phlegm and blood. He is taking the fumucil as prescribed by his pedia but the thing is, he is just blowing up whenever he intake the flumucil. Someone recommend to take the barley capsule. The instruction is to get the powder inside the capsule and mix it in with a little amount of water for about a tablespoon. Is it safe? Please advice..thanks!