Antibiotics do not help with toxins.
From what I can see by checking the code, valium helps preventing most of the effects that toxins can have. However, there’s no “cure” for the toxins in your body itself.
If I understand it correctly, toxins will decay over time (it will deduct 1 unit of toxins every 15 (ingame) minutes). Based on your stated status effect, you have between 950 and 1400 units of toxin in your body. So it will about take 10 days to get rid of all of the toxins in your body.
Pain is actually the lowest effect toxins have. The worst would be to randomly fall unconscious (if you get more than 1400 units of toxin built up).
Valium will suppress all effects, with the exception of pain.