Brief Answer:
Better don't take alpha lipoic acid.

Detailed Answer:
Hello dear welcome to Ask a doctor's service.
I read your query and here is my advice.

I think you should not use levothyroxine together with alpha lipoic acid.
Alpha lipoic acid may lower the levels of thyroid hormones and has an opposite effect to levothyroxine.
You can take gabapentin with levothyroxine as they don't interact with each other and don't effect the effects of one another.

Hope I have answered the question.
Let me know if I can assist you further.

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