From a medical (traditional physician standpoint) there is no better replacement for low testosterone levels than.... testosterone, however such over the counter/herbal alternatives include
pine pollen, tribulus terrestris, tongkat ali
However I'd also suggest having your thyroid checked out by your physician. That can cause the symptoms you've been describing
That is a simple blood test.
Those three herbal alternatives I described are available without a prescription however you should ideally discuss with the physician who was prescribing testosterone whether they think you are healthy enough to try them.
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Those alternatives I mentioned are over the counter.
Exercising would be your other natural alternative. I know you feel tired, but exercise raises your natural testosterone level too
I would suggest giving those three over the counter supplements a try and assessing after a few months whether they are working well enough for you.
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