Materia Medica by Kent

Again, if in a Merc. patient with diphtheria, tonsillitis, etc., the inflammation and pain begin on the LEFT side, and incline to remain there or spread to the right, the bin-iodide is indicated.

These two iodides have more rapid and greater induration beneath ulcers and chancres than MERC. and in old syphilitics the iodides are sometimes more useful.