Latisse is a prescription medication used to grow eyelashes. It’s FDA-approved to treat hypotrichosis of the eyelashes, which simply means inadequate or sparse lash growth. Applied once nightly to the upper lash line, it makes eyelashes longer, thicker, and darker over the course of several weeks.
How Latisse Was Discovered
Latisse exists because of a lucky side effect. The active ingredient, bimatoprost, was originally approved in 2001 as a glaucoma eye drop sold under the brand name Lumigan. Patients using Lumigan to lower eye pressure kept noticing something unexpected: their eyelashes were growing longer and fuller. Allergan, the manufacturer, recognized the cosmetic potential and developed a separate product, Latisse, specifically for topical application to the lash line. It remains the only FDA-approved prescription treatment for eyelash growth.
How It Makes Lashes Grow
Every eyelash goes through a growth cycle with an active phase (when the hair is actively lengthening) and a resting phase (when growth stops and the lash eventually falls out). Bimatoprost appears to extend the active growth phase, giving each lash more time to grow before it sheds. Some researchers believe it also shortens the resting phase, meaning new lashes start coming in faster. The combined effect is lashes that are visibly longer, thicker, and darker than they would be on their own.
What Results Look Like
Most people start noticing changes around 8 weeks, with full results at 12 to 16 weeks of consistent nightly use. In clinical trials, 78% of patients saw a meaningful improvement in overall eyelash prominence by week 16, compared to just 18% of those using a placebo. About a third of patients achieved a two-grade improvement on a clinical scale, meaning their results were dramatic enough to be clearly visible.
These results only last as long as you keep using the product. If you stop applying Latisse, your lashes gradually return to their previous appearance over a period of weeks to months as the natural growth cycle takes over again.
How to Apply It
Latisse comes in a small bottle with disposable sterile applicators. The routine is straightforward: once per night, you place a single drop on the applicator and brush it along the skin of your upper eyelid, right at the base of your lashes. The goal is to make the lash line feel lightly moist without any dripping. If solution runs beyond the lash line, you blot it away with a tissue.
A few rules matter here. You only apply it to the upper lash line, never the lower one. Applying it more than once a night won’t speed up growth or improve results. Each applicator is single-use, and you use a fresh one for each eye to keep things sterile. The product comes in either a 3 mL bottle (with 70 applicators, roughly a 5-week supply) or a 5 mL bottle (with 140 applicators, roughly a 10-week supply).
Common Side Effects
The most frequently reported side effects are eye redness, itching, and darkening of the skin around the eyes. The skin darkening tends to occur where the solution makes repeated contact, which is one reason you’re told to blot any excess and avoid applying it to the lower lid. For most people, skin darkening is reversible once they stop using the product.
A less common but more concerning side effect is a permanent change in iris color. Bimatoprost can increase brown pigmentation in the iris, and this change may not reverse after stopping treatment. The risk is higher for people with mixed-color eyes (hazel or green-brown) than for those with uniformly dark or blue eyes. Other reported effects include dry eyes, eye irritation, and a foreign body sensation.
Who Should Be Cautious
Latisse requires a prescription, so a provider will screen for potential issues before you start. People with active inflammation inside the eye, such as uveitis, need to use it carefully because bimatoprost can worsen the inflammation. Those who’ve had certain types of lens surgery or who have risk factors for swelling in the retina also need closer monitoring.
If you’re already using a prostaglandin-based eye drop for glaucoma (including Lumigan, which contains the same active ingredient), adding Latisse on top can interfere with your eye pressure management. In that case, your eye doctor needs to be involved and may monitor your pressure more closely. The only absolute contraindication is an allergy to bimatoprost or any of the inactive ingredients in the formula.
Who Uses Latisse
Some people seek out Latisse purely for cosmetic reasons, wanting fuller lashes without extensions or false lashes. Others have a genuine medical need. Eyelash loss can result from aging, chemotherapy, alopecia, thyroid conditions, or chronic rubbing and pulling. In all of these cases, Latisse works the same way: by extending the growth phase of whatever follicles are still active. It won’t regrow lashes from follicles that have been permanently destroyed, but for thinning lashes with functioning follicles, the results can be significant.
Because it’s prescription-only, you won’t find Latisse on drugstore shelves. Over-the-counter lash serums exist, but they don’t contain bimatoprost and aren’t held to the same efficacy standards. Some contain prostaglandin analogs or peptides that may offer modest benefits, but none have the clinical data that Latisse does.