What Do I Need To Know When Taking Doxycycline?

QUESTION- If taking doxycycline for a tick bite, what additional information do I need to know?

ANSWER- Patients should be advised that taking Doxycycline may cause sun sensitivity. Even hands on a steering wheel can be burned through the windshield. Be sure to wear a high SPF sunscreen on exposed skin and good protective eyewear. More sun protection information and ideas here.

Doxycycline should not be taken with milk or other dairy products since these products may inhibit absorption of the antibiotic. Doxycycline should also not be taken with antacids or supplements that contain calcium, iron, magnesium, or sodium bicarbonate because they may also inhibit absorption of the antibiotic. SOURCE

Doxycycline is generally not recommended for children under 8 years old since it may cause discoloration of their teeth. However, if Ehrlichiosis, Anaplasmosis, Spotted Fever and/or other TBDs are suspected that is considered an emergency, so use Doxycycline. UPDATE- A 2017 study indicates Doxycycline did not stain children's teeth. SOURCE

Doxycycline may promote yeast and fungal overgrowths which should be prevented and addressed if they occur. Taking a good probiotic between doses of Doxycycline and for a few weeks after stopping the medication has been recommended by Lyme treating doctors to help the gut.

Eat a full meal just before taking Doxycycline to help prevent indigestion, stomach pain and vomiting. Do not lay down for at least 30 minutes after taking the Doxycycline so it has time to disolve and disperse.

Birth control pills may not be as effective while taking Doxycycline. Additional precautions to prevent pregnancy should be considered.

Doxycycline passes into breast milk, but the extent of absorption of the drug in breast fed infants is unknown. Breastfeeding while using Doxycycline is not recommended.

Doxycycline use may cause liver problems or bruising in some cases. Report any concerns to your physician.

People taking Doxycycline should be advised that severe allergic reactions may occur and if there are any problems while taking Doxycycline, they should be reported to the doctor immediately!

Side effects of Doxycycline include:

  • Diarrhea
  • Difficulty swallowing
  • Drug rash
  • Esophageal ulcer
  • Esophagitis
  • Facial redness
  • Headache
  • Hives
  • Inflammation of the small intestine and colon (enterocolitis)
  • Lesions on the genitals or anus
  • Loss of appetite
  • Low blood sugar (hypoglycemia)
  • Low levels of white blood cells or platelets
  • Skin hyperpigmentation
  • Skin peeling (exfoliative dermatitis)
  • Tongue swelling
  • Tooth discoloration
  • Upper abdominal pain

Serious side effects of doxycycline include:

Drug rash with eosinophilia and systemic symptoms

Exacerbation of systemic lupus erythematosus

Hemolytic anemia


Low platelet count (thrombocytopenia)

Low white blood cell count (neutropenia)

Intracranial hypertension


Serum sickness

Toxic epidermal necrolysis

You may report side effects to FDA at 1-800-FDA-1088

For more information please check with your doctor or pharmacist.

Lucy Barnes


August 2018