Doxycycline oral capsule interactions: A detailed guide

This article describes possible interactions with doxycycline oral capsule. Interactions can cause a drug to have a different effect on the body than expected. Interactions can occur due to medications, alcohol, or certain health conditions.

To find coupon options for doxycycline and learn more about the drug, including its uses, see this article.

Doxycycline comes as tablets, capsules, and a liquid suspension (a type of liquid mixture) that you’ll swallow. It’s also available as a liquid solution that’s injected into your vein over time. Interactions of doxycycline may vary depending on the form of doxycycline you’re prescribed.

Other drugs and doxycycline

Before taking doxycycline oral capsule, tell your doctor and pharmacist about any prescription, over-the-counter, or other drugs you take. Doing so may help prevent possible interactions. If you’re concerned about possible interactions, talk with your doctor or pharmacist. They can tell you what medications you should not take with doxycycline.

Drugs that may interact with doxycycline oral capsule are listed below. This article doesn’t include all drugs that may interact with doxycycline.

Drugs that may interact with doxycycline oral capsule include:

• certain other antibiotics:
  • drug examples: amoxicillin (Amoxil, Larotid) and penicillin
  • what might happen: can make certain other antibiotics less effective
• certain antiepileptics:
  • drug examples: carbamazepine (Carbatrol, Tegretol, others) and phenytoin (Dilantin, Phenytek)
  • what might happen: can make doxycycline less effective
• certain blood thinners:
  • drug examples: warfarin (Jantoven)
  • what might happen: can increase the risk of side effects from blood thinners
• antacids:
  • drug examples: calcium carbonate (TUMS) and aluminum hydroxide/magnesium carbonate (Gaviscon)
  • what might happen: can make doxycycline less effective
• oral birth control:
  • drug examples: ethinyl estradiol/norgestimate (Estarylla, Sprintec, others) and ethinyl estradiol/levonorgestrel (Seasonale, Seasonique, others)
  • what might happen: can make oral birth control less effective
• bile acid sequestrants:
  • drug examples: colestipol (Colestid) and cholestyramine (Locholest, Prevalite)
  • what might happen: can make doxycycline less effective
• bismuth subsalicylate (Pepto-Bismol):
  • what might happen: can make doxycycline less effective

Other interactions and doxycycline

Interactions can occur with supplements, foods, vaccines, and some lab tests. Below you can learn whether doxycycline oral capsule has these interactions.

The information below doesn’t include all other possible interactions with doxycycline.

Doxycycline and food

Doxycycline oral capsule isn’t known to interact with foods. But this doesn’t mean interactions with foods can’t happen or won’t be identified later. 

Because of this, talk with your doctor or pharmacist about foods you should avoid during treatment with doxycycline.

Note: Calcium supplements may interact with doxycycline. Although dairy products contain calcium, these products aren’t expected to affect doxycycline. In fact, doxycycline’s drugmaker recommends taking the drug with milk or other foods to help prevent digestive side effects. To learn more, talk with your doctor or pharmacist about what to eat with doxycycline to avoid stomach upset.

Doxycycline and supplements

Before taking doxycycline oral capsule, tell your doctor and pharmacist about any supplements, herbs, and vitamins you take. Doing so may help you avoid possible interactions.

If you have questions about interactions that may affect you, talk with your doctor or pharmacist.

Doxycycline interactions with herbs

Doxycycline oral capsule isn’t known to interact with herbs. But this doesn’t mean interactions with herbs can’t happen or won’t be identified later.

Because of this, you should ask your doctor or pharmacist before taking any of these products during treatment with doxycycline.

Doxycycline interactions with vitamins and minerals

Doxycycline oral capsule may interact with vitamin C. The drug may also interact with mineral supplements such as calcium, iron, magnesium, aluminum, and zinc. Keep in mind that multivitamins often contain vitamin C and these minerals.

Taking doxycycline and vitamin C or any of the above mineral supplements may lead to low levels of doxycycline in your body. This could make doxycycline less effective than usual for treating your condition.

Because of this, your doctor may recommend taking doxycycline up to 6 hours before or after consuming vitamin C or any of the above mineral supplements. Talk with your doctor or pharmacist before taking any of these supplements during treatment with doxycycline.

Doxycycline and vaccines

Doxycycline oral capsule may interact with vaccines that help prevent tuberculosis (TB) or cholera.

Taking doxycycline and receiving a vaccine for TB or cholera could make either vaccine less effective. This may occur if you receive these vaccines while taking doxycycline or within 14 days of stopping doxycycline.

Because of this, you should talk with your doctor or pharmacist before receiving any vaccines during treatment with doxycycline.

Doxycycline and lab tests

Doxycycline oral capsule may interact with a urine test used to check for catecholamines. Among other conditions, this test checks for a type of tumor in the adrenal glands. 

Taking doxycycline and having this test may lead to a false positive result for certain tumors or other conditions. With a false positive result, a test shows a positive result for a condition that isn’t present.

Because of this, you should talk with your doctor or pharmacist before having the above urine test during doxycycline treatment. They can talk with you about other tests that check for certain conditions.

Doxycycline and cannabis or CBD

Doxycycline oral capsule isn’t known to interact with cannabis (commonly called marijuana) or cannabis products such as cannabidiol (CBD). But this doesn’t mean interactions can’t happen or won’t be identified later.

As with any drug or supplement, tell your doctor before taking cannabis with doxycycline.

Note: Cannabis is illegal at a federal level but is legal in many states to varying degrees.

When to avoid doxycycline

Certain health conditions or other factors could increase some risks with doxycycline oral capsule. Because of this, doctors may not prescribe doxycycline in these cases. These health conditions or other factors are called contraindications.

Here’s a doxycycline contraindication:

• Past allergic reaction to doxycycline. If you’ve had an allergic reaction to doxycycline oral capsule in the past, taking doxycycline may cause another allergic reaction.

Before starting treatment with doxycycline, tell your doctor if you’ve ever had an allergic reaction to the drug. They can recommend whether you should take doxycycline.

Alcohol and doxycycline

Doxycycline oral capsule is not known to interact with alcohol.

However, drinking alcohol while taking doxycycline may increase your risk of certain doxycycline side effects. Examples include loss of appetite, nausea, and diarrhea.

If you drink alcohol, talk with your doctor about whether it’s safe to consume it during your treatment
with doxycycline oral capsule.

Health factors and doxycycline

Certain medical conditions or other health factors may increase the risk of interactions with doxycycline oral capsule. Before taking doxycycline, tell your doctor about your health history. They’ll determine whether doxycycline is right for you.

Here’s a list of health conditions or other factors that might interact with doxycycline oral capsule:

• females* of reproductive age with overweight
• lupus (a type of autoimmune condition)
• a buildup of fluid around the brain
• pregnancy or breastfeeding
• past allergic reaction to doxycycline

* Sex and gender exist on spectrums. In this article, we use the term “female” to refer to a person’s sex assigned at birth.

Questions about doxycycline and interactions

Here you’ll find answers to some common questions about doxycycline and possible interactions.

Does doxycycline hyclate have different interactions than doxycycline monohydrate?

No, it isn’t likely. Doxycycline hyclate and doxycycline monohydrate each contain a different salt form of doxycycline. (Drugmakers sometimes use different salt forms to help your body absorb the drug.)

Because each drug contains doxycycline as its active ingredient, they’re expected to have the same interactions. (An active ingredient is what makes a drug work.)

To learn more about how doxycycline hyclate and doxycycline monohydrate compare, talk with your doctor or pharmacist.

Can I take doxycycline with a proton pump inhibitor?

Yes, if your doctor recommends it. Doxycycline isn’t known to interact with proton pump inhibitors (PPIs).

PPIs are used to treat conditions such as heartburn and gastroesophageal reflux disease (GERD). Examples include omeprazole (Prilosec) and esomeprazole (Nexium).

Keep in mind that doxycycline is known to interact with antacids, which are also used for heartburn and GERD. If you need treatment for these conditions, your doctor may advise you to take a PPI instead of an antacid.

To learn more about doxycycline and PPIs, talk with your doctor or pharmacist.

Preventing doxycycline interactions

You may be able to help avoid certain interactions with doxycycline oral capsule. Before taking this drug, you may want to discuss possible interactions with your doctor and pharmacist.

Things to consider include:

• Whether you drink alcohol or use cannabis.
• Other medications you take, as well as any vitamins, supplements, and herbs. Your doctor or pharmacist can help you fill out a medication list.
• What to do if you’re prescribed a new drug during your doxycycline oral capsule treatment.

Taking doxycycline exactly as prescribed can also help prevent interactions.

What to ask your doctor

If you have questions about doxycycline and possible interactions, talk with your doctor.

Questions you may want to ask your doctor include:

• What symptoms should I watch for with doxycycline drug interactions?
• Do other antibiotics have similar interactions?
• Do I need to space out any medications throughout the day to avoid interactions with doxycycline?

Disclaimer: Optum Perks has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.