When getting botox injections in the forehead does a patient feel the after effects?

Some patients will notice a "tight" feeling after Botox injection in a very small percentage may experience headache but for the most part there is very little in the way of the after effects following Botox injection

Thank you for your excellent question.  The first experience with Botox for patients is variable. Some patients have no effects, with little swelling, redness, or pain at the site of injections.  Some patients will have mild swelling and redness that may persist for up to 24 hours.  The most common side effect for patients is the development of a headache and I have seen that this is more common in patients used to furrowing their brow (those with significant vertical wrinkles between their eyes).  In general, however, the vast majority of patients return to work or their normal everyday activity comfortably after treatment.  

Around three days it is not uncommon to have a slight forehead ache, well before the botulinum toxin has started to work. It can feel numbish or slightly odd immediately after the injection and that is most likely the effect simply of an injection of fluid, but is not a concern at all. Some patients even tell me that they think it starts to work straight away, but again, that is just likely the effect of having had an injection and doing less movement afterwards because ever so slightly aching. So just beeing "aware" is within the very normal range of feelings.

Botox only affects the nerves responsible for motion.  Therefore, you will not feel numbness, pain or "weird" feelings where the Botox was injected.  However, many of my patients are aware of their inability to move their forehead muscles like normal.  Not weird, just aware.  And many of them tell me that, when the Botox wears off, the act of moving their forehead again feels "weird", like they have forgotten how it feels to move their forehead.  I have used Botox to "train" people NOT to move their forehead as much, because they can sense when they are moving their forehead, where they were unaware of it in the past.  Hope this helps.