Demeclocycline is a drug within the tetracycline family, and is widely used in the treatment of hyponatremia caused by syndrome of inappropriate antidiuretic hormone (SIADH). This drug is administered when fluid restriction alone is not adequate. The use of demeclocycline in SIADH actually utilizes a side effect of the drug, which is an antidiuretic hormone antagonist. In individuals without SIADH, demeclocycline can induce nephrogenic diabetes insipidus.
Minocycline is a tetracycline antibiotic which has a slightly broader spectrum than the other members of the group. This antibiotic is classified as a long-acting antibiotic, and has a half-life approximately two to four times that of other simple water-soluble tetracyclines. It is also is the most lipid-soluble, giving it the highest penetration into the brain and prostate. However, as a result, it is also associated with the greatest amount of CNS side effects, like vertigo.
Doxycycline is a tetracycline antibiotic that has a similar spectrum of coverage as other tetracyclines. It is commonly used in prophylaxis against malaria. Importantly, doxycycline is unique from other drugs in this class because it is fecally eliminated and can therefore be used in patients with renal failure.
Doxycycline is unique from other drugs in this class because it is fecally eliminated. Thus, it can be used in patients with renal failure.
Doxycycline is unique from other drugs in this class because it is fecally eliminated and can therefore be used in patients with renal failure.
Demeclocycline is a semisynthetic, specific tetracycline that is widely used in the treatment of hyponatremia caused by syndrome of inappropriate antidiuretic hormone (SIADH), when fluid restriction alone is not adequate. The use of demeclocycline in SIADH actually utilizes a side effect of the drug, which is an antidiuretic hormone antagonist. In individuals without SIADH, it can induce nephrogenic diabetes insipidus.
Chlamydia trachomatis is an obligate intracellular human pathogen. It is well known for its ability to cause human disease, including granular conjunctivitis, urethritis, and lymphogranuloma venereum. This organism is sensitive to tetracyclines, and this drug class can also be used to treat infections caused by Chlamydia pneumoniae and Chlamydia psittaci.
Rickettsial diseases are caused by a variety of obligate intracellular, gram-negative bacteria from the genera Rickettsia, Orienta, Ehrlichia, and Coxiella. Rickettsial infections that cause diseases in humans include Rocky Mountain spotted fever, typhus, Ehrlichiosis and Q fever. Tetracycline antibiotics are typically contraindicated in children, but an exception to this rule is when a child is suspected of having Rocky Mountain Spotted Fever. If there is a high clinical suspicion of Rickettsial infection in a patient, a tetracycline antibiotic should be started immediately.
Borrelia burgdorferi is a spirochete bacteria, which characteristically causes the symptoms of lyme disease. This bacteria is transmitted through the ixodes tick as a vector, which is required for its lifecycle. The classic presentation of lyme disease, or Borrelia burgdorferi infection after a tick bite, is an initial bulls-eye rash with central clearing. This rash is referred to as erythema migrans. After several weeks, the patient can experience a variety of neurologic or cardiac symptoms, including Bell's palsy and heart block.
Helicobacter pylori is a curved, gram-negative bacteria, which is flagellated. It is found in the upper gastrointestinal tract of over 50% of the world's population. H. pylori is the causative culprit of peptic ulcer disease and chronic gastritis. Tetracycline can be used as part of the “quadruple-therapy” regimen for treating H. pylori infections.
Mycoplasma pneumoniae is the organism that causes Mycoplasma pneumonia, also called walking pneumonia. The term “walking pneumonia” is used because X-ray findings often show a pulmonary infection before physical signs of atypical pneumonia are observable at all; thus, it is an occult pneumonia. This variety of pneumonia is an atypical pneumonia, and is spread through respiratory droplet transmission. It is called an atypical pneumonia because there is a protracted course, lack of sputum production, and extra-pulmonary symptoms as compared to typical pneumonia.
Picmonic's rapid review multiple-choice quiz allows you to assess your knowledge.
*Average video play time: 2-3 minutes
Unforgettable characters with concise but impactful videos (2-4 min each)