Somewhat slanting the topic here, but what happened to Tetracycline (non-synthetic)? One of the oldest, inexpensive treatments available – discontinued for, wha

Somewhat slanting the topic here, but what happened to Tetracycline (non-synthetic)? One of the oldest, inexpensive treatments available – discontinued for, what appears to be, no tangible reason. It was highly effective for all sorts of infections and was involved in some groundbreaking studies that tested its use as a cancer treatment, as well, was found to slow angiogenesis, treat rheumatoid arthritis, aging, depletion of collegen, acne, prostate cancer and treatment of fibromyalgia just to name a few. It's also a pretty reliable anti-inflammatory. For whatever reason, it is now hard to get or not available at all. Any insight into this?