There are different types of cough. Since after consulted your doctor and the problem still persist, you may want to bring her to consult TCM or you would want to consider to try the methods mentioned in these links: https://m.meishichina.com/article/212151/ https://www.hk01.com/%E8%A6%AA%E5%AD%90/272640/%E8%A6%AA%E5%AD%90%E9%A3%9F%E8%AD%9C-%E5%9B%9B%E6%AC%BE%E5%8C%96%E7%97%B0%E6%AD%A2%E5%92%B3%E9%80%9A%E9%BC%BB%E5%A1%9E%E9%A3%9F%E7%99%82%E6%8E%A8%E4%BB%8B-%E5%A4%A7%E4%BA%BA%E7%B4%B0%E8%B7%AF%E9%83%BD%E5%95%B1%E9%A3%B2 Wish your gal speedy recovery. Take care.
Im using organic balms like chest rubs and it helps !