Naphazoline is a decongestant used to relieve redness, puffiness, and itchy/watering eyes due to colds, allergies, or eye irritations (smog, swimming, or wearing contact lenses). It is known as a sympathomimetic (alpha receptor agonist) that works in the eye to decrease congestion.
Phenylephrine is a medication primarily used as a decongestant, to dilate the pupil, to increase blood pressure, and to relieve hemorrhoids. While marketed as a decongestant, taken by mouth at recommended doses it is of unclear benefit for hay fever.
Camphor is a waxy, flammable, transparent solid with a strong aroma. It is a terpenoid with the chemical formula C₁₀H₁₆O. It is found in the wood of the camphor laurel, a large evergreen tree found in Asia and also of the unrelated kapur tree, a tall timber tree from the same region.
Menthol is an organic compound made synthetically or obtained from the oils of corn mint, peppermint, or other mints. It is a waxy, crystalline substance, clear or white in color, which is solid at room temperature and melts slightly above.