New Era Comb H contains mag phos, nat mur and silica. Nat mur is the tissue salt most commonly linked with watery discharge, sinus sensitivity and seasonal irritation, mag phos is often chosen when there is spasm or tension around the face and head, and silica is traditionally used for sinus and tissue support.
That makes New Era Comb H a nose-and-sinus blend. It is usually chosen when hayfever or allergy symptoms come with sneezing, streaming eyes, blocked passages or head pressure. The added biotin is relevant here too, because biotin contributes to the maintenance of normal mucous membranes.
Nat mur is the ingredient that shapes this product most clearly, but the other two help round it out. Mag phos can matter when sinus pressure becomes uncomfortable, and silica is often included in tissue salt practice for lingering sinus issues.