Fluoroquinolones (drug interactions)
Fluoroquinolones are a class of antibiotics commonly prescribed for treating urinary tract infections and various other infectious diseases. However, they can have significant drug interactions that may affect their efficacy and safety. Certain minerals, such as calcium, iron, magnesium, aluminum, and zinc, can interfere with the absorption of fluoroquinolones; therefore, it is recommended to space the intake of these minerals at least two hours apart from the antibiotic doses. Herbal supplements like fennel, Dong quai, and St. John's wort may also pose risks, as they can either lower the antibiotic's effectiveness or increase the potential for side effects, like heightened sun sensitivity. Additionally, other substances, including ginkgo biloba and green tea extract, may interact adversely with fluoroquinolones. It is critical for individuals taking fluoroquinolones to communicate with their healthcare providers about all medications and supplements they are using to mitigate these interactions. Overall, while fluoroquinolones can be effective, awareness of potential interactions is essential for safe and effective treatment.
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Fluoroquinolones (drug interactions)
DEFINITION: Types of antibiotics used to treat urinary tract infections and other infectious diseases.
INTERACTIONS: Dong quai, fennel, St. John’s wort, calcium, iron, magnesium, zinc, aluminum, ginkgo biloba, green tea extract, various prescription medicines
DRUGS IN THIS FAMILY: Ciprofloxacin (Cipro), enoxacin (Penetrex), grepafloxacin (Raxar), levofloxacin (Levaquin), lomefloxacin (Maxaquin), norfloxacin (Noroxin), ofloxacin (Floxin), sparfloxacin (Zagam), trovafloxacin/alatrofloxacin (Trovan)
Minerals
Effect: Take at a Different Time of Day
The minerals calcium, iron, magnesium, aluminum, and zinc can interfere with the absorption of fluoroquinolones (and vice versa). Therefore, persons taking supplements of these minerals should take them at least two hours before or after taking the fluoroquinolone dose.
Fennel
Effect: Possible Harmful Interaction
The herb fennel appears to reduce blood levels of ciprofloxacin, possibly impairing its effectiveness. This finding comes from a placebo-controlled study in rats. Fennel might be expected to interfere similarly with other fluoroquinolone antibiotics.
Allowing two hours between taking ciprofloxacin and fennel should reduce the potential for an interaction, but that may not eliminate it. For this reason, it may be advisable to avoid fennel supplementation during therapy with ciprofloxacin or other antibiotics in this family.
Dong Quai, St. John’s Wort
Effect: Possible Harmful Interaction
Fluoroquinolone antibiotics have been reported to cause increased sensitivity to the sun, amplifying the risk of sunburn or skin rash. Because St. John’s wort and dong quai may also cause this problem, taking these herbal supplements during treatment with fluoroquinolone drugs might add to the risk. One should use sunscreen or wear protective clothing during sun exposure if one is also taking one of these herbs with a fluoroquinolone antibiotic. Experts recommend restricting fluoroquinolones to treat infections that do not respond to other antibiotics.
Other interactions include ginkgo biloba, which may increase the risk of seizure when taken with fluoroquinolones and green tea extract, which may inhibit its absorption, along with probiotics. Fluoroquinolones interact with myriad over-the-counter and prescription medicines, including antacids, caffeine, anticoagulants, non-steroidal anti-Inflammatory drugs, insulin, and corticosteroids. Individuals should inform their healthcare provider of all medications and supplements they are taking.
Bibliography
Baggio, Diva, et al. "Fluoroquinolone Antibiotics and Adverse Effects." Australian Observer, vol. 44, no. 5, pp. 161-64, Oct. 2021, doi.org/10.18773%2Faustprescr.2021.035. Accessed 15 Dec. 2022.
Campbell, N. R., and B. B. Hasinoff. "Iron Supplements: A Common Cause of Drug Interactions." British Journal of Clinical Pharmacology, vol. 31, no. 3, 1991, pp. 251-255.
"Ciprofloxacin and Alcohol/Food Interactions." Drugs.com, www.drugs.com/food-interactions/ciprofloxacin.html. Accessed 9 Sept. 2024.
Cunha, John P. "What Herbs Interfere with Medications? Interactions, Safety." eMedicineHealth, 12 Jan. 2023, www.emedicinehealth.com/what‗herbs‗interfere‗with‗medications/article‗em.htm. Accessed 9 Sept. 2024.
Lim, D., and M. McKay. "Food-Drug Interactions." Drug Information Bulletin, vol. 15, no. 2, 1995.