Tetracycline

Also indexed as: Achromycin, Actisite, Apo-Tetra, Economycin, Novo-Tetra, Nu-Tetra, Sumycin, Tetrachel, Topicycline

Combination drugs: Deteclo, Helidac

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Tetracycline is a member of the tetracycline family of antibiotics. Tetracycline is used to treat a wide variety of infections and severe acne.

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Summary of Interactions with Vitamins, Herbs, and Foods
In some cases, a herb or supplement may appear in more than one category, which may seem contradictory. For clarification, read the full article for details about the summarized interactions.

Beneficial May Be Beneficial: Depletion or interference—The medication may deplete or interfere with the absorption or function of the nutrient. Taking these nutrients may help replenish them.

Folic acid

Potassium

Vitamin B12

Vitamin B2

Vitamin B6

Vitamin C

Vitamin K*
Beneficial May Be Beneficial: Side effect reduction/prevention—Taking these supplements may help reduce the likelihood and/or severity of a potential side effect caused by the medication.

Bifidobacterium longum*

Lactobacillus acidophilus*

Lactobacillus casei*

Probiotics*

Saccharomyces boulardii*

Saccharomyces cerevisiae*

Vitamin K*
Beneficial May Be Beneficial: Supportive interaction—Taking these supplements may support or otherwise help your medication work better.

Probiotics*

Saccharomyces boulardii*

Vitamin B3 (Niacinamide only, for bullous pemphigoid and dermatitis herpetiformis)

Vitamin C*
Avoid Avoid: Reduced drug absorption/bioavailability—Avoid these supplements when taking this medication since the supplement may decrease the absorption and/or activity of the medication in the body.

Minerals (Aluminum, Calcium, Iron, Magnesium, Zinc)
Avoid Avoid: Adverse interaction—Avoid these supplements when taking this medication because taking them together may cause undesirable or dangerous results.

Berberine-containing herbs such as Goldenseal, Barberry, and Oregon grape
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An asterisk (*) next to an item in the summary indicates that the interaction is supported only by weak, fragmentary, and/or contradictory scientific evidence.

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Interactions with Dietary Supplements

Minerals
Many minerals can decrease the absorption of tetracycline, thus reducing its effectiveness. These minerals include aluminium (in antacids), calcium (in antacids, dairy products, and supplements), magnesium (in antacids and supplements), iron (in food and supplements), zinc (in food and supplements), and others.

Probiotics
A common side effect of antibiotics is diarrhoea, which may be caused by the elimination of beneficial bacteria normally found in the colon. Controlled studies have shown that taking probiotic microorganisms—such as Lactobacillus casei, Lactobacillus acidophilus, Bifidobacterium longum, or Saccharomyces boulardii—helps prevent antibiotic-induced diarrhoea.1

The diarrhoea experienced by some people who take antibiotics also might be due to an overgrowth of the bacterium Clostridium difficile, which causes a disease known as pseudomembranous colitis. Controlled studies have shown that supplementation with harmless yeast—such as Saccharomyces boulardii2 or Saccharomyces cerevisiae (baker’s or brewer’s yeast)3 —helps prevent recurrence of this infection. In one study, taking 500 mg of Saccharomyces boulardii twice daily enhanced the effectiveness of the antibiotic vancomycin in preventing recurrent clostridium infection.4 Therefore, people taking antibiotics who later develop diarrhoea might benefit from supplementing with saccharomyces organisms.

Treatment with antibiotics also commonly leads to an overgrowth of yeast (Candida albicans) in the vagina (candida vaginitis) and the intestines (sometimes referred to as “dysbiosis”). Controlled studies have shown that Lactobacillus acidophilus might prevent candida vaginitis.5

Vitamins
Tetracycline can interfere with the activity of folic acid, potassium, and vitamin B2, vitamin B6, vitamin B12, vitamin C, and vitamin K.6 This is generally not a problem when taking tetracycline for two weeks or less. People taking tetracycline for longer than two weeks should ask their doctor about vitamin and mineral supplementation. Taking 500 mg vitamin C simultaneously with tetracycline was shown to increase blood levels of tetracycline in one study.7 The importance of this interaction is unknown.

Taking large amounts of niacinamide, a form of vitamin B3, can suppress inflammation in the body. According to numerous preliminary reports, niacinamide, given in combination with tetracycline or minocycline, may be effective against bullous pemphigoid, a benign, auto-immune blistering disease of the skin.8 9 10 11 12 13 14 Preliminary evidence also suggests a similar beneficial interaction may exist between tetracycline and niacinamide in the treatment of dermatitis herpetiformis.15 16

Vitamin K
A few cases of excessive bleeding have been reported in people who take antibiotics.17 18 19 20 This side effect may be the result of reduced vitamin K activity and/or reduced vitamin K production by bacteria in the colon. One study showed that people who had taken broad-spectrum antibiotics had lower liver concentrations of vitamin K2 (menaquinone), though vitamin K1 (phylloquinone) levels remained normal.21 A few antibiotics appear to exert a strong effect on vitamin K activity, while others may not have any effect. Therefore, one should refer to a specific antibiotic for information on whether it interacts with vitamin K. Doctors of natural medicine sometimes recommend vitamin K supplementation to people taking antibiotics. Additional research is needed to determine whether the amount of vitamin K1 found in some multivitamins is sufficient to prevent antibiotic-induced bleeding. Moreover, most multivitamins do not contain vitamin K.

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Interactions with Herbs

Berberine-containing herbs
Berberine, a chemical extracted from goldenseal (Hydrastis canadensis),barberry (Berberis vulgaris), and Oregon grape (Berberis aquifolium), has been shown to have antibacterial activity. One double-blind study found that giving 100 mg of berberine at the same time as 500 mg of tetracycline four times daily led to a reduction of the efficacy of tetracycline in people with cholera.22 Berberine may have decreased the absorption of tetracycline in this study. Another double-blind trial did not find that berberine interfered with tetracycline in cholera patients.23 Until more studies are completed to clarify this issue, berberine-containing herbs should not be taken simultaneously with tetracycline.

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Interactions with Foods and Other Compounds

Food
Tetracycline should be taken on an empty stomach, one hour before or two hours after any other food, drugs, or supplements, with a full glass of water.24

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References
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