Why Can't I Apply Latisse to Lower Lid or Eyebrows?

Thanks for the question -
I would caution people a bit about using Latisse in off label applications. Specifically, the lower lashes get some of the medication when you close your eyes (the reason Allergan recommends using it at night). Placing medication on both lashes is likely to increase the dosage of the medication you're getting.
Dosage studies conducted by Allergan show that increasing the dosage or frequency of application does not change how quickly your lashes come in. What it does do is increase potential side effects (most commonly eye irritiation which can be serious).
Remember that Latisse is a drug, not a cosmetic. Becareful about using it in non-approved ways.
I hope this helps.

Latisse is only recommended for use on the upper lash line. To use Latisse in another manner would be off label and I would not recommend doing that. 

The FDA has approved Latisse for use on the upper
eyelashes.At this time all other uses
are considered off label.Despite this
many practitioners have utilized Latisse on the lower eyelashes and eyebrows
with encouraging results.Under
these circumstances, many physicians are reluctant to use Latisse on the lower
eyelashes or eyebrow.With more study
the FDA will hopefully lift these restrictions.

It is recommended for the upper lash line only because there is some transference of the product to the lower lash line, every time you blink. This allows one bottle to last longer. It also reduces the risk of undesirable side effects when limiting usage, particularly dryness and itchiness.Latisse is only FDA approved for the eyelashes, however there are reports that it can achieve an improvement for brows as well.

There’s a longer explanation possible here, but the short version is this: the FDA has only approved LATISSE® to be marketed for use in the upper lashes. That being said, I am sure that some patients (and some doctors) have experimented with "off-label" uses of LATISSE® like thickening the eyebrows or lower lashes. Some of them have probably seen positive effects, too. That being said, though, it’s important to understand that LATISSE® has only been studied and approved by the results of clinical trials for use on the upper lashes, and there’s little information about the effects of using it elsewhere.

Wondering if Latisse can be applied on areas other than the upper lashes? The mechanism by which Latisse works suggest that it would work on any hair follicle on the body.  However, not all hair follicles on the body (eyebrows, eyelashes, beard, scalp, etc) have the same physiology leading to patterns of loss that differ and may make the formulation that works on upper lashes ineffective elsewhere.  Latisse was evaluated for and FDA approved for use on the upper lashes only.  Notwithstanding, I have personally seen patients independent of recommendations, apply Latisse to lower lashes and eyebrows and see some improvements.

You can apply latisse to your eyebrows, and they will probably become longer and thicker. 

You really don't need to apply latisse to your lower lids.  When you apply to your upper lids, some of the medicine does migrate to the lower lashes.  Also, if you apply to the lower lids, you are at more risk for irritation.

Latisse for lash growth. Latisse will grow hair anywhere it is applied. So careful application  is important, particularly in the lower eyelid. Although I haven't recommended using Latisse on the lower lashes, many patients have started doing so and have been pleased with the results.

Latisse is FDA approved only for the upper eyelashes. There may be potential side effects when used in other ways for eyelid or eyebrow hair growth. Speak with a specialists to determine if this product is appropriate for you. Best of luck.

There are several potential complications of Latisse that are limited by restricting it's use to the upper lid.
Namely, darkening of the iris or the skin. It can also cause undesireable hair growth on the cheek.
 

Recommendations are to use Latisse as indicated in the initial FDA approval for hypotrichosis of the lower eyelids. Clearly, the FDA and Allergan will be closely evaluating an indication for the lower eyelids as well. At this time, lower eyelash use is off-label and in theory, should work as effectively as the upper eyelash. If you plan on using on the lower eyelashes, make sure you are receiving close follow-up by a physician.