Hopkins ABX Guide

Tetracycline Antibiotic

What is Tetracycline and When It is Used?

Tetracycline is an antibiotic that is derived from actinobacteria of the Streptomyces genus. Discovered in the mid-1940s by American plant physiologist Benjamin Minge Duggar (1872-1956), the medication is used to treat a wide range of infections but it is also used to produce several derivatives of the natural antibiotic. These together with the original derivate form the class of tetracycline antibiotics.

Unfortunately, efficacy of this group of broad-spectrum antibiotics has declined significantly over the years due to the growing incidence of antibiotic resistance. Nonetheless, tetracycline and other antibiotics in the group of tetracyclines remain the first-line treatment for a wide range of bacterial infections.

Natural tetracycline and its semisynthetic derivatives are used for treatment of acne, rosacea, Rocky Mountain spotted fever, Lyme disease, syphilis, chlamydia, Mycoplasma pneumonia (walking pneumonia), leptospirosis, shigellosis (Shigella infection), malaria, leprosy, plague, anthrax, brucellosis, and more. Besides being used for treatment of a wide range of infections, tetracycline is also used as bone growth marker in human biopsies and as biomarker in wild animals.

How Tetracycline is Taken/Administered?

The antibiotic is available in the form of tablets, capsules, syrup, suspension and powder for suspension, and is either taken orally or administered as an injection. The dosage and duration of tetracycline therapy depend on the type of infection and its severity.

Side Effects of Tetracycline

Many side effects of tetracycline are mild and don’t require medical help because they often go away on their own after completing the treatment. Some of the most common side effects include nausea with or without vomiting, loss of appetite, diarrhoea, black hairy tongue, tooth discolouration, mouth sores, headache, dizziness and sore throat. Some tetracyclines can also cause skin photosensitivity (increased sensitivity to sunlight), ringing in the ears (tinnitus), easy bruising/bleeding, secondary infection (yeast infection in long-term use), inflammation of the liver and acute hepatitis manifested by yellowing of the skin and eyes, and muscle pain.

Tetracycline antibiotics may rarely also cause very dangerous hypertension (high pressure) inside the skull, severe diarrhoea and serious allergic reaction (rash, swelling, breathing difficulties). Symptoms of these potentially very serious conditions/reactions require immediate medical intervention. Patients taking tetracyclines should also contact their doctor right away if developing other severe or disturbing symptoms.

Tetracyclines shouldn’t be used during pregnancy and mustn’t be given to children younger than 8 years. Older adults are more sensitive to the medication’s effects and therefore, they should be closely monitored while on tetracycline therapy.