IF he has been to a doctor, and it is just a regular nasty, persistent cough... oo masakit sa ulo, and your ribs eventually hurt everytime you cough... hindi ako naniniwala sa Atchi ko before... pero, with my cough meds prescribed by the doc... I take oregano. The oregona leaves that are totally green, hindi yung may white edges.
Get a few leaves, wash well, steam just so the leaves soften... then mash with a spoon to get the katas... take 1 tablespoon in the morning and then in the evening. Works for us, 1 week, wala nang cough. Sometimes, 3 days lang.
Basta when you take it, do not drink nor eat anything until after 30minutes.