-antacids
-barbiturates
-birth control pills
-bismuth subsalicylate
-carbamazepine
-methoxyflurane
-other antibiotics
-phenytoin
-vitamins that contain iron
-warfarin

They need to know if you have any of these conditions:
-liver disease
-long exposure to sunlight like working outdoors
-stomach problems like colitis
-an unusual or allergic reaction to doxycycline, tetracycline antibiotics, other medicines, foods, dyes, or preservatives
-pregnant or trying to get pregnant
-breast-feeding

Tell your doctor or health care professional if your symptoms do not improve.

Do not treat diarrhea with over the counter products. Contact your doctor if you have diarrhea that lasts more than 2 days or if it is severe and watery.

Do not take this medicine just before going to bed. It may not dissolve properly when you lay down and can cause pain in your throat. Drink plenty of fluids while taking this medicine to also help reduce irritation in your throat.

This medicine can make you more sensitive to the sun. Keep out of the sun. If you cannot avoid being in the sun, wear protective clothing and use sunscreen. Do not use sun lamps or tanning beds/booths.

Birth control pills may not work properly while you are taking this medicine. Talk to your doctor about using an extra method of birth control.

If you are being treated for a sexually transmitted infection, avoid sexual contact until you have finished your treatment. Your sexual partner may also need treatment.

Avoid antacids, aluminum, calcium, magnesium, and iron products for 4 hours before and 2 hours after taking a dose of this medicine.

If you are using this medicine to prevent malaria, you should still protect yourself from contact with mosquitos. Stay in screened-in areas, use mosquito nets, keep your body covered, and use an insect repellent.

Keep out of the reach of children.

Store at room temperature, below 30 degrees C (86 degrees F). Protect from light. Keep container tightly closed. Throw away any unused medicine after the expiration date. Taking this medicine after the expiration date can make you seriously ill.