Acid, Carbolic.
Acid, Nitric: when expectoration is free and too copious.
Aconite: one-half to 1 min. every hour at the commencement of an acute catarrhal attack.
Actæa Racemosa: in acute catarrh and bronchitis when the more active symptoms have subsided.
Alkalies: to render mucus less viscid.
Amber Oil: counter-irritant over spine in children.
Ammoniacum: very useful in old people.
Ammonium Acetate.
Ammonium Carbonate: Where much expectoration and much depression; or where the mucus is very viscid and adherent.
Apomorphine: causes a copious expectoration in the early stage.