Most serums take between 8-12 weeks. But, you have to use it consistently otherwise the growth cycle will go back to normal when you stop. Note that eyebrows grow at a slower rate compared to scalp or body hair.

How long do eyebrow serums last?

I'll likely have to keep using RapidBrow to maintain the effects. At $50 a tube (which lasts about two months), that can be a steep investment over time, especially if you only see minimal improvements.

What happens when you stop using eyebrow serum?

If you stop using the serum, your brows will return to their normal growth cycle, and you'll stop seeing the crazy good results. ... While serums stimulate your brows' follicles, plucking can harm and even destroy follicles for good—which means you could undo all the work and money you put into the process.