What are the differences between minocycline, doxycline and tetracycline?

Tetracycline: This group of antibiotics started with the discovery of tetracycline. Changing the formula of its chemical composition gave birth to the new derivatives - Minocycline and doxycycline. Bacterial coverage remains the same but dosage convenience was the result. The original tetracycline had to be taken 4x a day while the newer generation is dosed as 2x a day due to their longer duration of action.

See below: They are all 3 antibiotics of the tetracycline class and have very similar antibacterial spectrums. Minocycline and Doxycycline can be given safely to patients with renal failure. Minocycline gets high nasal and sinus levels and is good for MRSA colonization treatment. Doxycycline can cause photosensitivity but is otherwise well tolerated.