Most listings allow up to four applications per day. One product specifically directs dosing every 6–8 hours with a maximum of four doses daily.
Some formulations act very quickly (about 1 minute for certain drops) and many are described as fast‑acting; durations reported in listings range from a few hours up to about 8–12 hours depending on the product.
Some products are labeled paraben‑free; others are described as bleach‑free and dye‑free, and some are specifically labeled BAK‑free in addition to being bleach‑ and dye‑free. Check each product label for exact free‑of claims.