I am only 22 years old, and would like to start Botox injections of the forehead. Is 22 too young to start Botox?

BoTox, and all forms of Botulinum Toxin A, work by blocking the reuptake of acetylcholine at the neuromuscular junction. By doing so, it inhibits transmission of signals from one neuron to the next at whichever junction it is working on (e.g., neuro junction, sweat gland junction, etc.) The duration of BoTox is typically 3-4 months on average. It can take up to 7 days for it to take effect. BoTox is an excellent modality to reduce wrinkles caused by facial animation of the forehead, glabellar area, and crow's feet. Nowadays, patients are starting smaller procedures earlier  versus having a drastic change later in life with a dramatic surgical procedure.  Once these bother you enough to consider, have a consultation to discuss the risks and benefits of such.  Thank you for the question! Hope this helps!

It is quite popular for younger patients to get Botox as a preventative measure. The key is to find an injector who is gentle and conservative, as you don't need too many units to achieve what you'd like.

Botox can be used as a preventative measure. Seek a consult from an experienced injector who will fully understand your desired result. At 22, the Dr / injector can assess your face regardless of age and inform you of an appropriate treatment. 

I do not think that this is too young to start Botox.  I would be conservative with the treatment to keep you looking natural but it can prevent wrinkles from forming later in life.  Also remember to stay out of the sun and avoid smoking.  This will help too!

Botox is believed to play a preventative role as well as its well recognized ability to reduce lines caused by contraction of muscles.  If you have strong muscle action, even if you do not have deep lines, it is not unreasonable to undergo preventative treatment.