Doxycycline is one of the most commonly prescribed antibiotics in the United States: In 2019, this drug was prescribed more than 21 million times.
Certain foods, medications, herbal treatments, and supplements may prevent doxycycline from being fully absorbed by the body.
In some cases, they could render doxycycline ineffective.
Dairy can make it harder for the body to absorb doxycycline.
In this article, I’ll explain more about this interaction, and tell you how much dairy is safe to eat while taking this medication.
I’ll also tell you more about doxycycline—what it is, what it’s used to treat, how to take it, and its potential side effects.
And I’ll list some other foods, beverages, supplements, and medicines you should avoid while taking doxycycline.
What Is Doxycycline?
It can also be used following anthrax exposure, in the treatment of some types of acne, and to prevent malaria.
As a member of the tetracycline family of drugs, doxycycline works by decreasing a bacteria’s ability to make proteins.
As a result, bacteria can’t grow or flourish, giving your immune system a chance to fight the infection.
In the United States, doxycycline may be prescribed under brand names including Acticlate, Doryx, Mondox, or Vibramycin, or as a generic.
It is typically prescribed in tablet or capsule form, but is also available as an injection.
Doxycycline is used to treat a wide range of infections caused by bacteria, including:
- Urinary tract infections
- Bacterial intestinal infections
- Bacterial respiratory infections
- Eye infections
- Certain sexually transmitted infections (STIs)
- Periodontitis (gum disease)
Doxycycline can also be used to prevent malaria.
Doxycycline only treats infections caused by bacteria.
Doxycycline And Dairy
How does dairy affect doxycycline?
Studies have found that dairy makes it harder for the body to absorb doxycycline,thus reducing its effectiveness.
In 1987, scientists found that study participants who included a “milk drink” with their pill absorbed significantly less of the medication than those who took doxycycline on an empty stomach.
Calcium in dairy reactions with doxycycline, forming a substance that is harder for your intestines to absorb.
When this happens, less doxycycline is absorbed by your gastrointestinal tract.
It is not clear how much this affects how well doxycycline will work, so the CDC says to avoid dairy for a few hours before and after taking your doxycycline dose.
Can I have any dairy while taking doxycycline?
You don’t have to remove dairy from your diet entirely while taking doxycycline.
To ensure your dose is effective, though, avoid dairy products for at least two hours before and after your dose.
Some common dairy products you should avoid within two hours of doxycycline include milk, butter, cream, cheese, ghee, whey, whey protein, ice cream, yogurt, and frozen yogurt.
How To Take Doxycycline
Doxycycline should be taken with plenty of fluids, in an upright position, and according to the dose specified on your prescription label.
Never increase or decrease the dosage or the duration of your prescription, other than when instructed by your provider.
Doing so may increase your chance of experiencing side effects.
It’s best to space out your doses of doxycycline evenly and take it at a scheduled time every day.
This helps maintain a constant level of the antibiotic in your body and reduces the likelihood of forgetting to take your medication.
Finishing the entire course of doxycycline is important too, even if your symptoms start to improve. This will ensure the infection is completely treated.
Like all prescription medications, doxycycline comes with a patient information leaflet.
Read and follow these instructions carefully, as recommendations may vary according to different brands of doxycycline.
Other Things To Avoid While Taking Doxycycline
Research suggests that foods rich in iron and iron supplements may impact your body’s ability to absorb doxycycline.
Avoid eating iron-rich foods like sardines, beef, eggs, kale, tofu, and spinach around the same time as taking doxycycline.
As with dairy, eat these at least two hours before or after taking your medicine.
If you’re fighting an infection and taking antibiotics, it’s best to abstain from alcohol.
Drinking, especially heavily, is associated with a weakened immune system and will slow down your recovery.
If you have a medical history of liver problems or chronic alcohol consumption, and you mix alcohol with doxycycline, the antibiotic will be less likely to work well.
Using alcohol while taking antibiotics can also increase the risk of side effects like stomach irritation and nausea.
Getting typhoid and cholera vaccines
Doxycycline can make some vaccinations less effective at protecting you from disease, including the live, attenuated typhoid vaccine.
The World Health Organization (WHO) recommends that antibiotics are stopped from three days before to three days after receiving this vaccine.
If you are unsure if this applies to you, inform the healthcare professional administering your vaccine of your recent doxycycline use.
They will be best placed to advise you on whether to proceed.
Certain medications, supplements And multivitamins
If you take several medications at once, a reaction may occur between the two drugs—this is called an interaction.
Sometimes, this can be harmful.
At this time, 191 drugs are identified as not mixing well with doxycycline, including bismuth and warfarin.
Iron supplements, multivitamins, calcium supplements, and antacids can also interact with doxycycline.
Tell your doctor or prescriber about all prescription medicines, OTC medicines, and supplements that you take.
Potential Side Effects Of Doxycycline
More serious side effects are rare, but can happen.
If you experience the following symptoms, seek urgent medical help:
- Unexplained bruising or bleeding (including repetitive nosebleeds) combined with a sore throat, high temperature, and general tiredness
- Severe diarrhea that contains mucus or blood and lasts longer than 4 days
- Ringing or buzzing in your ears
- Joint or muscle pain which started after taking the medicine
- Severe headaches, vomiting, and problems with your vision
- A sore or swollen mouth, lips, or tongue
- Severe stomach pain, with or without bloody diarrhea, nausea, or vomiting
- Pain or difficulty in swallowing, a sore throat, acid reflux, chest pain, or a reduced appetite
- Severe allergic reaction (signaled by hives, difficulty breathing, and swelling of the face/throat)
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Frequently Asked Questions
K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.
K Health has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references.
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Oral Doxycycline in the Management of Acne Vulgaris. (2015).
Can I drink alcohol while taking antibiotics? (2021).
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