Alcohol Denat., Butane, Isobutane, Propane, Aluminum Starch Octenylsuccinate, Silica, Parfum (Fragrance).

Any dry shampoo used regularly will cause some buildup. Wash properly at least once between each day you use it, and use a clarifying shampoo periodically to clear the scalp.

If white residue is an issue for you, yes. For lighter hair where white cast doesn't show, a cheaper option works fine. For darker hair or anyone who finds standard dry shampoos obvious, the formula difference makes a significant practical difference.

Not as a substitute for washing. Dry shampoo refreshes the surface but doesn't clean the scalp. Two to three times between washes is the sensible guideline.