Doxycycline

• Doxycycline is used to treat a variety of bacterial infections such as infections of the respiratory tract and the lungs (like bronchitis, pneumonia, etc.)
• Urinary tract infections
• Sexually transmitted diseases such as urethral, cervical (lower part of the uterus), anal infections and ulcers in the genital region (chancroid)
• Doxycycline is used as second line treatment for gonorrhea and syphilis
• Pimples and infections of sweat glands (acne vulgaris)
• Eye infections
• Rickettsial infections (fever, chills, severe headache, body pains, loss of appetite, etc.) such as rocky mountain spotted fever, Q fever and tick fevers
• Other infections like malaria, cholera, psittacosis (parrot fever – fever, chills, vomiting, body pains, diarrhea), melioidosis (cough, fever, chest pain, headache) and other similar bacterial infections
• Prevention of infectious diseases such as scrub typhus (fever, body aches, and rashes), leptospirosis (high fever, chills, body aches, bleeding) and traveler’s diarrhea

When should one not use Doxycycline

Common side effects of this drug are:

• Extreme skin sensitivity to light causing skin rashes, itching, redness, sunburn (serious, but uncommon)
• Swollen tongue, loose motions, fever, cramps (pseudomembranous colitis); itching near the genital regions or anus; worsening of previously existing allergic reactions; decreased blood cell counts causing easy bleeding, infections, sore throats; ringing in the ears; liver problems (jaundice or yellowing of skin and eyes), irritation of the pancreas
• Discoloration of teeth, black hairy tongue, discoloration of thyroid gland, mouth and lip sores, stomach pain, loose motions, indigestion, vomiting, ulcers of the oesophagus (food tube), headache, blurred or permanent loss of vision, bulging head in infants; kidney problems, body aches, detachment of nails etc. (uncommon)
• Severe skin reactions causing rashes, redness, patches on the skin, blisters, ulcers, skin peeling, like burning (Stevens-Johnson syndrome); fever chills, headache, body pains, rashes (Jarisch-Herxheimer reaction), or allergic reactions causing fever, rashes, blood cell abnormalities (DRESS syndrome) – serious, but rare
• Severe allergic reactions causing swelling of face, throat, lips, swallowing or breathing difficulty with or without rashes, skin blisters, low blood pressure (serious, but rare)

Other General Warnings

• Liver disease
• A genetic disorder of blood resulting in defective hemoglobin, purple patches on the skin and nerve damage (porphyria)
• A type of muscle weakness (myasthenia gravis)
• Sensitivity to light
• A disorder of the immune system causing rashes on the face, fever, joint and body pains, hair loss (systemic lupus erythematosus)

How Does It Work?

Interactions with other medicines

• Use the following medicines with caution:
• Warfarin (blood-thinning agent, used to prevent blood clots)
• Penicillin and Rifampicin (antibiotics)
• Antacids or Sucralfate (reduce acidity of stomach)
• Sleeping tablets (Phenobarbital, etc.)
• Carbamazepine, Phenytoin or Primidone (to treat seizures)
• Methoxyflurane (used for anesthesia)
• Cyclosporine (to suppress immune response)
• Ergotamine or methysergide (for migraine)
• Kaolin (for loose motions)
• Methotrexate (to treat cancers, joint pains)
• Quinapril (for high blood pressure)
• Birth control pills
• Retinoids (vitamin A compounds used for skin growth)
• Typhoid vaccines

Interactions with food items

Overdose

Missed a Dose

• If you forget to take a dose, follow the regular dose schedule. Do not take a higher or double dose to make up for the missed dose
• Doxycycline is ordinarily taken once or twice a day. Hence, make sure there is at least a 12-hour gap between 2 dosages