Hi Erika28,
Interesting question -I've been thinking exactly the same. It feels like the effect weakens towards the end, and my experience is that its not the amount of gel, but the efficacy. The amount only decreases at the very end of the bottle, while the weakening of the effect seems to happen already somewhere around 50 doses.
Its really annoying as consistency of the dose is absolutely critical for many of us who are sensitive to even minor fluctuations.
Haven't found a way to resolve this, though, other than using gel from two bottles and combining the new and old, i.e. 1 pump from the new, 1 pump from the old.
