Doxycycline is an antibiotic which has been used for over 50 years to treat a wide variety of bacterial infections. It has been shown to generally be safe and well-tolerated, but it has also been shown in multiple studies to have anti-cancer effects.

Doxycycline and Cancer

There are several key actions of doxycycline which are of interest to us. First, it inhibits a key group of enzymes known as matrix metalloproteinases (MMPs). We know that MMPs are responsible for cancer growth and spread. Second, doxycycline has been shown to kill cancer stem cells (CSCs). Cancer stem cells are key players in cancer growth and spread, and very few treatments have been shown to target them. In addition to these findings, doxycycline makes these CSCs more susceptible to damage to radiation therapy.

Doxycycline and Vitamin C

Research has shown us that doxycycline actually changes the way cancer cells behave metabolically. More specifically, cancer cells exposed to doxycycline are affected at the mitochondrial level, and become committed to an exclusively glycolytic (sugar burning) pathway. This makes cancer cells susceptible to a second “hit,” this time from IV vitamin C. The vitamin C acts to deplete this pathway, effectively starving cancer cells. The doxycycline plus IV vitamin C combination was found to be approximately 10 times as effective in killing cancer cells compared to doxycycline alone.

Antibiotics and Gut Health

As we know, antibacterial agents can deplete beneficial bacteria in the gut. However, probiotics have been shown to negate this side effect, and as a result we always include a robust probiotic supplement with this approach.