Why should Latisse be used at night?

Latisse can be applied any time, as long as it can be absorbed. The main point is to apply when you don't have make-up on, and when the lash is undisturbed. For most, this means nighttime, when makeup has been removed, and when the eyes won't be rubbed. If you wanted to apply in the morning, it would still work. You could also apply at night, but simply put on after your cream, and apply the cream in a way so it is not right on your lash. 

The manufacturer’s instructions
recommend using Latisse® at night because it’s presumed that your face is clean
and free from makeup when you’re going to bed, making it easier for the product
to penetrate at the root of your eyelashes. However, if you have a personal
preference for using it during the day, that should be fine. My recommendation
would be to wash your face, apply serums, moisturizers and then apply Latisse®.
Then, wait at least 10 minutes or so before applying eye makeup to give the
product time to absorb.

Thank you for your excellent question.  Latisse can be successfully applied during the day instead of the night for the exact reason you describe - lower penetration or dilution when used with eye creams.  Additionally, if you toss and turn during the night you may have some of the medication wear off before it has sufficient time to work.  Hope this helps.

When to use Latisse is a great question!  I have been recommending Latisse for eyelash growth in Orange County even BEFORE it was Latisse (when it was just sold as Lumigan, a glaucoma eye drop), for over 10 years.  I discovered that it worked better and also had less side effects when used in the morning. When women use oil-based eye makeup removers in the evening, I believe they interfere with absorption of Latisse.  Also, we have found, after selling over 10,000 bottles of Latisse, that our patients have a much lower incidence of side effects (redness, itching, pigmentation of the skin) when they apply it with a very fine eyeliner brush (which we supply as a gift with every bottle of Latisse) in the morning.  The rationale behind this is that less gets on the skin and when applied the morning it is not accidentally rubbed into the surrounding skin during sleep, which can occur when your face is pressed on a pillow.  Feel free to contact my OCdermatology office if you have any questions.

Latisse can actually be applied during the morning as well as the night. The main concern is that the eyelashes and eyes need to be clean and make up free. Some patients prefer applying in the morning where they no that they will not rub their eyes as they might at night. It comes down to what is best for you.

Great question.  It is recommended to apply Latisse at night, when the face is clean, makeup and contact lenses are removed and all nightly facial products are already applied.  Also, when applied at night, the benefits of Latisse affecting lower lash growth is higher, since the eyes are closed while sleeping.  It is a personal decision, however, as to when to apply Latisse.  As long as the eyes and lashes are clean and make-up free, Latisse can be applied either in the A.M. or the P.M.