Botox - Are the Lines Supposed to Completely Disappear? AND my First Shot Lasted One Month

Hi SS.  In terms of how long your Botox should last, one month is definitely too little.  When properly dosed you should receive 3-4 months of benefit.

In regard to the line that was being treated.  It almost sounds by your description that the line is horizontal because you say it goes "across" the bridge of the nose.  Botox is primarily used to treat vertical lines between the eyes, but may still work if you have a horizontal line.  The other possibility is that you have a deeper vertical crease that may need some dermal filler to treat completely.  We use Restylane or Juvederm usually in this case.  See the pictures in the link below to see a female with a deep furrow line that required both Botox and dermal filler (4th set of pictures down).

Botulinum toxin should last about 3 months but every patient is different in terms of the number of units they require for good effect and the duration of effect. Botulinum toxin weakens muscles and softens lines created by muscle movement. It does not treat lines that are imprinted in the skin. These lines can require dermal filler to be eliminated. Sometimes botulinum toxin and dermal fillers are used simultaneously.
Best,Stephen Weber MD, FACS

Quite frequently it takes 30-40 years for lines to develop and it is unlikely that they will completely disappear with treatment. Furthermore, some pateints are very expressive and when they believe that the botox effect has worn off, I observe use of other "substitute" muscles that have been recruited and are responsible for the persistence or recurrence of the lines.