Applies to doxycycline: oral capsule, oral capsule extended release, oral powder for suspension, oral syrup, oral tablet, oral tablet delayed release

Along with its needed effects, doxycycline may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking doxycycline:

Incidence not known

• Blistering, peeling, or loosening of the skin
• bloating
• chills
• clay-colored stools
• constipation
• cough
• dark urine
• decreased appetite
• diarrhea
• diarrhea, watery and severe, which may also be bloody
• difficulty with swallowing
• dizziness
• fast heartbeat
• feeling of discomfort
• fever
• headache
• hives, itching, puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
• hives or welts, itching, or rash
• increased thirst
• indigestion
• inflammation of the joints
• joint or muscle pain
• large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
• loss of appetite
• nausea
• numbness or tingling of the face, hands, or feet
• pain in the stomach, side, or abdomen, possibly radiating to the back
• red skin lesions, often with a purple center
• redness and soreness of the eyes
• redness of the skin
• severe stomach pain
• sore throat
• sores, ulcers, or white spots in the mouth or on the lips
• stomach cramps
• stomach pain or tenderness
• swelling of the feet or lower legs
• swollen, painful, or tender lymph glands in the neck, armpit, or groin
• tightness in the chest
• unusual tiredness or weakness
• unusual weight loss
• vomiting
• yellow eyes or skin

Some side effects of doxycycline may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Incidence not known

• Back, leg, or stomach pains
• bleeding gums
• blood in the urine or stools
• blurred vision
• bulging soft spot on the head of an infant
• change in the ability to see colors, especially blue or yellow
• chest pain, discomfort, or burning
• cracks in the skin
• decrease in vision
• difficulty breathing
• discoloration of the thyroid glands
• double vision
• general body swelling
• heartburn
• increased sensitivity of the skin to sunlight
• loss of heat from the body
• lower back or side pain
• nosebleeds
• pain or burning in the throat
• pain with swallowing
• painful or difficult urination
• pale skin
• pinpoint red spots on the skin
• rash with flat lesions or small raised lesions on the skin
• red, swollen skin
• redness or other discoloration of the skin
• redness, swelling, or soreness of the tongue
• scaly skin
• severe nausea
• severe sunburn
• tooth discoloration
• unusual bleeding or bruising
• vomiting blood

Applies to doxycycline: injectable powder for injection, oral capsule, oral delayed release capsule, oral delayed release tablet, oral kit, oral powder for reconstitution, oral syrup, oral tablet, oral and topical kit

Very common (10% or more): Headache (up to 26%)

Common (1% to 10%): Sinus headache

Rare (0.01% to 0.1%): Bulging fontanels (in infants), benign intracranial hypertension (pseudotumor cerebri [symptoms include blurred vision, scotomata, diplopia]), tinnitus

Frequency not reported: Hypoesthesia, increased intracranial pressure, paresthesia, somnolence, stupor, taste loss, drowsiness, amnesia, paresthesias of body areas exposed to sunlight, phrenic nerve paralysis after sclerotherapy

Postmarketing reports: Pseudotumor cerebri, headache, dizziness

Benign intracranial hypertension resulting in permanent loss of vision has been reported.

A 70-year-old female patient with no significant medical history suddenly developed a severe headache followed by vomiting about 15 minutes after the initial dose of this drug. The patient also experienced memory dysfunction; she could not remember the events of the afternoon prior to the dose of this drug and could not retain the information after she was reminded. The incident lasted about 30 minutes and she was transported to the hospital for further evaluation. No further cause, such as intoxication or trauma, could be elicited. Once at the hospital, the patient was able to remember the events of the afternoon and could retain new information, but amnesia regarding the events of the 30 minutes following the onset of the headache persisted. The patient's laboratory results, computerized tomography scan, MRI scan, cerebrospinal fluid, and electroencephalogram showed no pathology. When the patient was discharged 2 days later, the amnesia for the 30 minutes continued. After elimination of other symptomatic causes, the amnesia was concluded to be due to this drug because of the close relation of the dose and the onset of symptoms.

Very common (10% or more): Common cold (up to 22%), influenza symptoms (up to 11%)

Common (1% to 10%): Injury/accidental injury, pain, infection, fungal infection, influenza

Rare (0.01% to 0.1%): Candida infection/candidiasis, flushing, retrosternal pain

Frequency not reported: Malaise, overgrowth of nonsusceptible organisms (superinfection)

Postmarketing reports: Asthenia

Very common (10% or more): Nausea (up to 13.4%)

Common (1% to 10%): Nausea/vomiting, toothache, tooth disorder, dyspepsia, diarrhea, periodontal abscess, acid indigestion, upper abdominal pain, abdominal distention, abdominal pain, stomach discomfort, dry mouth

Uncommon (0.1% to 1%): Gum pain, heartburn/gastritis

Rare (less than 0.1%): Glossitis, dysphagia, enterocolitis, inflammatory lesions (with candidal/monilial overgrowth) in the anogenital region, esophagitis, esophageal ulcerations, pancreatitis, pseudomembranous colitis, Clostridium difficile colitis, stomatitis

Frequency not reported: Clostridium difficile-associated diarrhea, esophageal irritation, ulceration, epigastric burning, black hairy tongue, tooth discoloration/adult tooth staining, vomiting, enamel hypoplasia, staphylococcal enterocolitis

Postmarketing reports: Bloody diarrhea, colitis, constipation, superficial tooth discoloration

Numerous cases of esophageal ulceration have been reported. In most cases, the patients had taken their medication at bedtime, usually without enough liquid. Patients often presented with severe retrosternal pain and difficulty swallowing. Ulcerations generally resolved within a week after discontinuing the drug. In 1 case report, severe hiccups of 4-day duration associated with esophagitis followed the first dose of this drug.

Esophagitis and esophageal ulcerations have been reported in patients taking the capsule or tablet formulations of tetracycline-class antibiotics. Most of these patients took the drug immediately before going to bed.

Common (1% to 10%): Joint pain/arthralgia, back pain/back ache

Uncommon (0.1% to 1%): Muscle pain/myalgia

Common (1% to 10%): Nasopharyngitis, sore throat, sinus congestion, coughing, sinusitis, bronchitis, nasal congestion, pharyngolaryngeal pain

Frequency not reported: Bronchospasm

Common (1% to 10%): Rash (including maculopapular rash, erythematous rash), photosensitivity reaction/dermatitis

Rare (0.01% to 0.1%): Erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis, exfoliative dermatitis, photoonycholysis, drug reaction with eosinophilia and systemic symptoms (DRESS)

Frequency not reported: Nail discoloration, phototoxicity, photoallergic reaction, morbilliform rash, onycholysis, pustular rash

Postmarketing reports: Pruritus, urticaria

Tetracyclines:

-Frequency not reported: Hyperpigmentation

In a double-blinded study, this drug was found to be more phototoxic than minocycline and demeclocycline. Paresthesias of the body areas exposed to sunlight may be early signs of sunburn reactions.

A case report of a possible photoallergic reaction described scaly erythema and vesicles on the face and neck associated with administration of this drug. Upon rechallenge, a flare with erythema, itching, and burning occurred in the same area.

Another case report was documented in Australian troops treated with 100 mg daily for malaria prophylaxis while on deployment in East Timor, a group of islands within the Malaysian archipelago located close to the equator. Of the 135 troops, 22 exhibited phototoxic reactions to low doses of this drug that resembled severe sunburn with erythematous plaques on the sun-exposed areas. The troops used a sunscreen containing oxybenzone.

An 11-year-old boy treated with this drug for brucellosis was evaluated for painless brown nail discoloration. This drug was initiated for brucellosis but stopped when the boy developed photosensitivity, but 15 days after the initiation of therapy brown nail discoloration developed. Other than the brown discoloration, the boy's physical condition was normal and the discoloration disappeared within 1 month.

Common (1% to 10%): Menstrual cramps, bacterial vaginitis, vulvovaginal mycotic infection

Uncommon (0.1% to 1%): Vaginal infection

Frequency not reported: Vaginal itch, vaginitis

Postmarketing reports: Vaginal candidiasis/moniliasis, anogenital moniliasis

Common (1% to 10%): Hypertension, increased blood pressure

Frequency not reported: Phlebitis (with IV administration)

Common (1% to 10%): Increased AST

Rare (0.01% to 0.1%): Abnormal hepatic function, hepatic failure, hepatitis, hepatotoxicity, jaundice

Frequency not reported: Acute hepatocellular injury, cholestatic reactions, cholestatic hepatitis, fatty liver degeneration, transient increases in liver function tests

Hypoglycemia in a nondiabetic patient has been reported.

Common (1% to 10%): Increased blood LDH, increased blood glucose

Rare (0.01% to 0.1%): Decreased appetite, porphyria

Frequency not reported: Hypoglycemia, anorexia

Common (1% to 10%): Anxiety

Frequency not reported: Confusion, depression, hallucination

Common (1% to 10%): Anaphylactic reaction (including angioedema, exacerbation of systemic lupus erythematosus, pericarditis, hypersensitivity, serum sickness, Henoch-Schonlein purpura, hypotension, dyspnea, tachycardia, peripheral edema, urticaria)

Frequency not reported: Hypersensitivity reactions (including urticaria, angioneurotic edema, anaphylactic shock, anaphylaxis, anaphylactoid reactions, anaphylactoid purpura, serum sickness, hypotension, pericarditis, exacerbation of systemic lupus erythematosus, dyspnea, peripheral edema, tachycardia)

Postmarketing reports: Mild allergic reactions

Rare (0.01% to 0.1%): Hemolytic anemia, thrombocytopenia, neutropenia, eosinophilia

Frequency not reported: Increased prothrombin time, leukopenia, thrombocytopenic purpura

Rare (0.01% to 0.1%): Increased BUN/blood urea (dose-related)

Frequency not reported: Acute renal failure

The long-term use of tetracyclines has been associated with microscopic brown-black discoloration of the thyroid gland; abnormal thyroid function has not been reported.

Rare (0.01% to 0.1%): Microscopic brown-black discoloration of the thyroid gland

Frequency not reported: Diplopia, papilledema, loss of vision (associated with drug-induced benign intracranial hypertension), conjunctivitis, periorbital edema

Tetracyclines:

-Frequency not reported: Autoimmune syndromes