Do not take Doxycycline capsules and tell your doctor if you:
are allergic (hypersensitive) to doxycycline, other similar antibiotics (such as minocycline or tetracycline) or any of the other ingredients in the capsule, are giving it to a child under 12 years old. Take special care with Doxycycline capsules and tell your doctor if you:
have liver disease or are taking medicines which affect your liver, have porphyria (a genetic disorder of the blood), suffer from myasthenia gravis, a condition characterised by muscle weakness, difficulty chewing and swallowing and slurred speech, are sensitive to sunlight, have systemic lupus erythematosus (SLE) a condition characterised by a rash (especially on the face), hair loss, fever, malaise and joint pain.
Taking other medicines
Please tell your doctor or pharmacist if you are taking or have recently taken any other medicines, including medicines obtained without a prescription. Especially: warfarin or other anticoagulants (to stop the blood clotting), penicillin or rifampicin (to treat infections),
medicines such as antacids containing aluminium, calcium or magnesium or other medicines containing iron, bismuth or zinc salts. Do not take at the same time as Doxycycline capsules, as absorption of doxycycline may be reduced,
phenobarbital, carbamazepine, phenytoin or primidone (to treat epilepsy), oral contraceptives (the pill), methoxyflurane (an anaesthetic), if you need an operation, tell your doctor or dentist you are taking Doxycycline capsules, ciclosporin (used following organ transplants).
Pregnancy and breastfeeding
If you are pregnant, planning to become pregnant or are breast feeding, ask your doctor or pharmacist for advice before taking any medicine as doxycycline could harm the baby.
Side effects
Like all medicines, Doxycycline capsules can cause side effects, although not everybody gets them.
Stop taking the capsules immediately and seek urgent medical advice if: you notice that your skin is very sensitive to light (you may get a skin rash, itching, redness or severe sunburn when out in sunlight or after using a sun bed).
Contact your doctor at once if the following reactions happen: wheeziness, difficulty in breathing, fever, sudden swellings of the face, lips, throat, tongue, hands or feet, fast heart rate, low blood pressure, rash or itching (especially affecting the whole body), pericarditis (inflammation of the membrane surrounding the heart), swollen tongue, watery diarrhoea, fever and cramps (pseudomembranous colitis), soreness and itching around the back passage and/or genital areas, inflammation around the vagina, or thrush of the vagina or mouth, worsening of systemic lupus erythematosus (SLE).
Tell your doctor if you notice any of the following side effects or notice any other effects not listed: Blood: altered numbers of certain types of blood cells, you may notice that you bruise easily, have nose bleeds, or suffer from infections and sore throats, porphyria (sensitivity of the skin to sunlight, inflammation of nerves and stomach pains). Glands and hormones: discolouration of thyroid tissue (does not affect thyroid function). Central nervous system: headache, increased pressure in the skull (severe headaches, blurred and/or double vision, blind spots), permanent loss of vision, bulging fontanelles (soft spot on head) of infants. Ears: tinnitus (ringing or buzzing in the ears). Gastrointestinal tract: stomach pain, loss of appetite, feeling or being sick, heartburn, diarrhoea, difficulty swallowing, sore or painful tongue or mouth, inflammation and/or ulcers of the gullet, discolouration or underdevelopment of teeth. Liver: changes in liver function tests, inflammation of the liver (hepatitis), jaundice (yellowing of the skin or white of the eyes), liver failure and inflammation of the pancreas (pancreatitis). Skin: severe skin reactions such as erythema multiforme (circular, irregular red patches), Stevens-Johnson syndrome (rash with flushing, fever, blisters or ulcers), toxic epidermal necrolysis (reddening, peeling and swelling that resembles burns). Muscles and bones: muscle or joint pain. Kidneys: an increase in urea in the blood.
If you notice any side effects, they get worse, or if you notice any not listed, please tell your doctor or pharmacist.