One thing can be said about the drug https://www.imedix.fr/medicaments/doxycycline.html Doxycycline - a broad-spectrum antibiotic. The price of the drug is ideal for its use in various clinical manifestations. It is prescribed in a long course and is quite effective in many diseases. I read somewhere that this antibiotic is out of date. The patient may have persistent ""addiction"" to it. Quite banal, it may not work. Guys, is there anyone to whom this drug did not help?