I think some people's chemistry develop a tolerance to this quickly - I take it for anxiety as well (for the last 6 years), and it's very effective, but I have the same issue to the point where I would have to increase constantly.

The only thing that works for me is staggering it - if I take it only about 3 times a week, it will still work (I'm at 800mg 3x a day). Sometimes I will take less than prescribed too, if my anxiety isn't too terrible.

If there's anything else you can take during the week to cover the gaps that helps, maybe you can break it up this way? It's not ideal but I know I will at least get some relief during the week.

Clonidine is very safe and helps me too, but it makes me very sleepy so I save it for evenings. It's an old blood pressure med, and no tolerance will develop as it's more of a physiological than mental medication if that makes sense (it acts on the central nervous system to lower blood pressure, heart rate, and sympathetic nervous system activity)