You can take doxycycline hydrochloride tablets when you have your period. Doxycycline tablets are antibiotics that are very good for treating mycoplasma infections and chlamydia infections, so if you have these two pathogenic infections, you can use the drug for the corresponding treatment. If you take this medication when you have your period, it will not affect your period itself, so you can take it without worrying, and if the clinical symptoms have disappeared after your period, you should go to the hospital in time for a review, and if the laboratory tests have turned negative, you can stop using the medication for treatment. Because mycoplasma and chlamydia can be transmitted through sexual contact, it is important not to have sexual intercourse until the laboratory tests have turned negative during the illness to avoid cross-infection.