What is tetracycline, and how does it work (mechanism of action)?
Tetracycline is a broad spectrum antibiotic, that is, it is active against many different types of bacteria. It is effective against Hemophilus influenzae, Streptococcus pneumoniae, Mycoplasma pneumoniae, Chlamydia psittaci, Chlamydia trachomatis, Neisseria gonorrhoeae, and many others. Tetracycline prevents growth of bacteria by preventing the bacteria from manufacturing proteins that they need to survive. The first drug of the tetracycline family, chlortetracycline, was introduced in 1948.
Is tetracycline available as a generic drug?
Do I need a prescription for tetracycline?
What are the side effects of tetracycline?
Tetracycline is generally well-tolerated. The most common side effects are:
Tetracycline may cause discoloration of teeth if used in patients below 8 years of age. Exaggerated sunburn can occur with tetracycline (photosensitivity). Therefore, sunlight or sunlamp exposure should be minimized during treatment.
What is the dosage for tetracycline?
Food or dairy products reduce the absorption of tetracycline. Therefore, tetracycline should be taken at least two hours before or after meals. For most infections, tetracycline is taken two to four times daily for 7 to 14 days. The usual adult dose is 1-2 g/day in 2 or 4 divided doses.
Is tetracycline safe to take if I'm pregnant or breastfeeding?
What else should I know about tetracycline?
What preparations of tetracycline are available?
Capsules: 250 and 500 mg; Oral Suspension: 125 mg/5 ml (teaspoon).
How should I keep tetracycline stored?
Tetracycline should be stored below 30 C (86 F).
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Tetracycline (Sumycin, discontinued) is a medication that is used for treating several types of infections. Examples of infections include infections of the respiratory tract, urinary tract, and skin; urethritis, typhus, Rocky Mountain spotted fever, certain sexually transmitted diseases (STDs), acne, anthrax, cholera, and H. pylori. Side effects and drug interactions should be reviewed prior to taking tetracycline (Achromycin, Sumycin).
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Rosacea Quiz: Test Your Medical IQ
Think acne and rosacea are the same? Think again. Take the Rosacea Quiz to learn all about this inflammatory skin condition.
Acne (Pimples) Quiz: Test Your Medical IQ
Acne is the most common skin disorder in the world. If you suffer from acne, you are not alone and many treatment options are...
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A sexually transmitted disease caused by Treponema pallidum, a microscopic organism called a spirochete. See a picture of...
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An infection of the hair follicles of the skin. See a picture of Folliculitis and learn more about the health topic.
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Related Disease Conditions
Acne is a localized skin inflammation as a result of overactivity of oil glands at the base of hair follicles. This inflammation, depending on its location, can take the form of a superficial pustule (contains pus), a pimple, a deeper cyst, congested pores, whiteheads, or blackheads. Treatments vary depending on the severity of the acne.
Boils (Skin Abscesses)
A boil is a skin abscess, a collection of pus localized deep in the skin. There are several different types of boils. Among them are the following: furuncle or carbuncle, cystic acne, hidradenitis suppurativa, and pilonidal cyst.
Bullous pemphigoid is a skin disease that causes blistering eruptions on the skin's surface and sometimes affects the inner lining of the mouth. Symptoms include severe itching and burning sensations. Treatment involves topical cortisone and sometimes high doses of cortisone. Severe cases may require immune-suppression drugs such as azathioprine.
Canker sores are a common complaint, and are small ulcers on the inside of the mouth. Canker sores aren't contagious (as opposed to cold sores), and typically last for 10-14 days usually healing without scarring. A variety of things cause canker sores, for example, medications (aspirin, beta-blockers, NSAIDs, high blood pressure medication, and antibiotics); injury to the mouth from dental work, braces, or sports accidents; acidic foods; allergies; and diseases or conditions like celiac disease, Crohn's disease, and lupus. Canker sores can be cure with home remedies, and prescription and OTC topical and oral medication.
Learn more about cavities including symptoms, treatment, and prevention. See how tooth decay, plaque, and bacteria contribute to the creation of cavities and how regular brushing and flossing can help prevent dental caries.
Clostridium Difficile Colitis (Antibiotic-Associated Colitis, C. difficile colitis)
Clostridium difficile (C. difficile) is a bacterium, and is one of the most common causes of infection of the colon. C. difficile spores are found frequently in hospitals, nursing homes, extended care facilities, and nurseries for newborn infants. They can be found: on bedpans, furniture, toilet seats, linens, telephones, stethoscopes, fingernails, rings, floors, infants' rooms, and diaper pails. They even can be carried by pets. Antibiotic-associated (C. difficile) colitis is an infection of the colon caused by C. difficile that occurs primarily among individuals who have been using antibiotics. Treatment for C. difficile colitis includes: hydration, replenishment of electrolyte deficiencies, discontinuing the antibiotic that caused the colitis, and using antibiotics to eradicate the C. difficile bacterium.
H. pylori (Helicobacter Pylori) Infection
Helicobacter pylori (H. pylori) is a bacteria that causes chronic inflammation (gastritis) of the inner lining of the stomach, and also is the most common cause of ulcers worldwide. About 50% of people in the world carries or is infected with H. pylori. Common symptoms of H. pylori infection are occasional abdominal discomfort, bloating, belching or burping, and nausea and vomiting. H. pylori infection is difficult to eradicate, and treatment is with two or more antibiotics.
Malaria is a disease that is spread by the bite of an infected Anopheles mosquito. Malaria symptoms include fever, chills, nausea, vomiting, and body aches. Treatment involves supportive care and antibiotics.
Peptic Ulcer (Stomach Ulcer)
Peptic or stomach ulcers are ulcers are an ulcer in the lining of the stomach, duodenum, or esophagus. Ulcer formation is related to H. pylori bacteria in the stomach, use of anti-inflammatory medications, and cigarette smoking. Symptoms of peptic or stomach ulcers include abdominal burning or hunger pain, indigestion, and abdominal discomfort after meals. Treatment for stomach ulcers depends upon the cause.
Pinkeye, also called conjunctivitis, is redness or irritation of the conjunctivae, the membranes on the inner part of the eyelids and the membranes covering the whites of the eyes. These membranes react to a wide range of bacteria, viruses, allergy-provoking agents, irritants, and toxic agents.
Pregnancy Planning (Tips)
Pregnancy planning is an important step in preparation for starting or expanding a family. Planning for a pregnancy includes taking prenatal vitamins, eating healthy for you and your baby, disease prevention (for both parents and baby) to prevent birth defects and infections, avoiding certain medications that may be harmful to your baby, how much weight gain is healthy exercise safety and pregnancy, travel during pregnancy.
Rosacea is a skin disease that causes redness of the forehead, chin, and lower half of the nose. In addition to inflammation of the facial skin, symptoms include dilation of the blood vessels and pimples (acne rosacea) in the middle third of the face. Oral and topical antibiotics are treatments for rosacea. If left untreated, rhinophyma (a disfiguring nose condition) may result.
Scleroderma is an autoimmune disease of the connective tissue. It is characterized by the formation of scar tissue (fibrosis) in the skin and organs of the body, leading to thickness and firmness of involved areas. Scleroderma is also referred to as systemic sclerosis, and the cause is unknown. Treatment of scleroderma is directed toward the individual features that are most troubling to the patient.
Sexually Transmitted Diseases in Women (STDs)
Sexually transmitted diseases (STDs) are among the most common infectious diseases in the United States. STDs can be spread through any type of sexual activity involving the sex organs, the anus or mouth, or through contact with blood during sexual activity. Examples of STDs include, chancroid, chlamydia, gonorrhea, granuloma inguinale, lymphogranuloma venereum, syphilis, genital herpes, genital warts, trichomoniasis, pubic lice (crabs), and scabies. Treatment is generally with antibiotics; however, some STDs that go untreated can lead to death.
Urinary Tract Infection (UTI)
A urinary tract infection (UTI) is an infection of the bladder, kidneys, ureters, or urethra. E. coli, a type of bacteria that lives in the bowel and near the anus, causes most UTIs. UTI symptoms include pain, abdominal pain, mild fever, urinary urgency and frequency. Treatment involves a course of antibiotics.
Mycobacterium marinum (M. marinum) is bacteria found in fresh and saltwater that can infect the skin through cuts or scrapes, causing granulomas to appear on the skin near the site of infection. This infection may be treated with a long course of oral antibiotics.
Weber-Christian disease is a rare inflammatory disease that affects the body's fat tissues. It's also known as relapsing febrile nodular panniculitis syndrome and idiopathic lobular panniculitis. The disorder appears on the skin as red or purple tender, raised lumps. The thighs and lower legs are the most frequently affected areas. Other symptoms may include: nausea, vomiting, weight loss, joint pain, and abdominal pain. Though there is no cure for the disease, inflammation may be treated with various anti-inflammatory medications.
COPD (Chronic Obstructive Pulmonary Disease)
COPD or chronic obstructive pulmonary disease is a lung condition caused by smoking tobacco, exposure to secondhand smoke, and/or air pollutants. Conditions that accompany COPD include chronic bronchitis, chronic cough, and emphysema. Symptoms of COPD include shortness of breath, wheezing, and chronic cough. Treatment of COPD includes GOLD guidelines, smoking cessation, medications, and surgery. The life expectancy of a person with COPD depends on the stage of the disease.
Anthrax is a deadly infectious disease that may be transmitted to humans by infected animals or by biological warfare. There are three types of anthrax: cutaneous, inhalation, and gastrointestinal. Symptoms of cutaneous anthrax include a swollen glands, muscle ache, headache, fever, nausea, vomiting, and a red-brown raised spot that enlarges, blisters, and hardens, forming an ulcer crater with black crust. Symptoms of inhalation anthrax are flu-like and may progress to respiratory distress, shock, coma, and death. Symptoms of gastrointestinal anthrax include loss of appetite, bloody diarrhea, and abdominal pain. Treatment for cutaneous anthrax involves penicillin, tetracycline, erythromycin, and ciprofloxin. Inhalation anthrax necessitates treatment with IV therapy with antibiotics.
Chlamydia in Women
Chlamydia is the most common sexually transmitted disease in the U.S. Signs and symptoms of chlamydia, a bacterial infection, include vaginal discharge, abdominal pain, burning with urination, blood in the urine, and feelings of urinary urgency and frequency. Untreated chlamydia can cause pelvic inflammatory disease (PID), increased risk of ectopic pregnancy, and infertility. Chlamydia is diagnosed with a culture or by identification of the genetic material of the bacteria. Treatment of chlamydia consists of a course of antibiotics.
Syphilis in Women
Syphilis is a sexually transmitted disease (STD) caused by a spiral-shaped type of bacteria known as a spirochete. There are three stages of syphilis with distinct symptoms. During first stage of syphilis, a painless ulcer known as a chancre forms. Irreversible organ damage can occur during the late stage of syphilis. Special blood tests are used to diagnose syphilis. Syphilis infection is treated with penicillin. Condom use can often prevent syphilis.
Pseudotumor Cerebri (Idiopathic Intracranial Hypertension)
Pseudotumor Cerebri (intracranial hypertension) is a condition where there is an increase in pressure of fluid surrounding the brain and spinal cord (cerebrospinal fluid or CSF) mimicing a brain tumor. The cause is unknown. The most common symptom is headache but also include eye-pain, vision loss and double vision. Pseudotumor cerebri is diagnosed with MRI or CAT scans and treated by discontinuing offending medications (if applicable), weight loss and diuretic medications. The condition can also be helped by repeated drainage of spinal fluid using the lumbar puncture.
Yaws is an infectious disease that mainly occurs in the tropical areas of South and Central America, Asia, Africa, and the Pacific Islands. The disease is caused by a bacterium called Treponema pertenue, which causes lesions that look like bumps on the skin of the feet, hands, face, and genital area. Yaws is treated with penicillin or another antibiotic.
Pregnancy and Drugs (Prescription and OTC)
Taking prescription medications or over-the-counter drugs or supplements should be discussed with your doctor. There are some medications that have been found to cause no problems in pregnancy, however, medications such as Accutane for acne, should never be taken during pregnancy.
Heart Attack Prevention
Heart disease and heart attacks can be prevented by leading a healthy lifestyle with diet, exercise, and stress management. Symptoms of heart attack in men and women include chest discomfort and pain in the shoulder, neck, jaw, stomach, or back. Women experience the same symptoms as men; however, they also may experience: Extreme fatigue Pain in the upper abdomen Dizziness Fainting Leading a healthy lifestyle with a heart healthy low-fat diet, and exercise can help prevent heart disease and heart attack.
Sun-Sensitive Drugs (Photosensitivity to Drugs)
Sun sensitivity (photosensitivity) is an inflammation of the skin induced by the combination of medications or substances and sunlight. The effect on the skin is redness, which looks similar to a sunburn. Generally, these reactions are either phototoxic or photoallergic. Phototoxic drugs are more common than photoallergic drugs. Symptoms of phototoxic reactions are a burning and stinging sensation and then redness. Symptoms of photoallergic reactions are itching, redness, swelling, and blisters of the affected area. Treatment generally is discontinuation of the medication and topical application of creams.Treatment generally is discontinuation of the medication and topical application of creams.
STDs in Men
Sexually transmitted diseases (STDs) are infections transmitted during sexual contact. They may be caused by viruses, bacteria, or parasites. STDs in men cause no symptoms or symptoms like genital burning, itching, sores, rashes, or discharge. Common infections that are sexually transmitted in men include gonorrhea, chlamydia, syphilis, hepatitis C and B, genital warts, human papillomavirus (HPV), and genital herpes. Some STDs in men are treatable while others are not. STDs are diagnosed with tests that identify proteins or genetic material of the organisms causing the infection. The prognosis of an STD depends on whether the infection is treatable or not. Use of latex condoms can help reduce the risk of contracting an STD but it does not eliminate the risk entirely.
Cholera is an infectious disease characterized by intense vomiting and profuse watery diarrhea and that rapidly lease to dehydration and often death. Cholera is caused by infection with the bacteria Vibrio cholerae, which may be transmitted via infected fecal matter, food, or water.
Pleurisy, an inflammation of the lining around the lungs, is associated with sharp chest pain upon breathing in. Cough, chest tenderness, and shortness of breath are other symptoms associated with pleurisy. Pleurisy pain can be managed with pain medication and by external splinting of the chest wall.
Antibiotic Resistance (Drug Resistance, Antimicrobial Resistance)
Antibiotics are medications used to kill or slow the growth of bacteria and some fungi. The definition of antibiotic resistance is the ability of bacteria to change (mutate) and grow in the presence of a drug (an antibiotic) that would normally slow its growth or kill it. These antibiotic-resistant bacteria and fungi become harder to treat. Antibiotic-resistant infections can lead to longer hospital stays, higher treatment costs, and more deaths.
Dry eyes are caused by an imbalance in the tear-flow system of the eye, but also can be caused by the drying out of the tear film. This can be due to dry air created by air conditioning, heat, or other environmental conditions. Treatment may involve self-care measures, medications, or rarely, surgery.
Vancomycin-Resistant Enterococci (VRE)
Vancomycin-resistant enterococci (VRE) infection is the most common type of infection acquired by patients while hospitalized. Patients at risk for VRE are those who are already ill, and hospitalized, including individuals with diabetes, elderly, ICU patients, kidney failure patients, or patients requiring catheters. Enterococci can survive for months in the digestive tract and female genital tract. Other risk factors for acquiring VRE include those how have been previously treated with vancomycin and combinations of other antibiotics. Treatment of VRE is generally with other antibiotics other than vancomycin. Prevention of VRE can be achieved by proper hand hygiene.
Rocky Mountain Spotted Fever (RMSF)
Rocky Mountain spotted fever is a tick-borne disease that causes symptoms and signs such as fever, rash, headache, and muscle aches. The antibiotic doxycycline is the standard treatment for Rocky Mountain spotted fever.
Plague (Black Death)
Plague is an infectious disease caused by the bacteria Yersinia pestis. Transmission to humans occurs via fleas that have bitten infected rodents. There are three forms of plague that infect humans: bubonic, septicemic, and pneumonic. Antibiotics are the standard treatment for plague.
Folliculitis (Symptoms, Causes, Transmission, Home Treatment, and Cure)
Folliculitis is a skin condition that causes small red bumps to form around the hair follicles. Skin bacteria such as Staphylococcus and Pseudomonas may infect the follicles. Treatment involves over-the-counter bacterial washes, topical antibiotics, and/or topical steroids.
Jock itch is an itchy red rash that appears in the groin area. The rash may be caused by a bacterial or fungal infection. People with diabetes and those who are obese are more susceptible to developing jock itch. Antifungal shampoos, creams, and pills may be needed to treat fungal jock itch. Bacterial jock itch may be treated with antibacterial soaps and topical and oral antibiotics.
Ingrown hairs may be caused by improper shaving, waxing, or blockage of the hair follicle. Symptoms and signs of ingrown hairs include itching, tenderness, and small red pus bumps. Ingrown hairs usually heal on their own, but topical antibiotics, chemical depilatories, and hair-removal laser may be used in the treatment of ingrown hairs.
Tularemia (rabbit fever) is an infection caused by the Francisella tularensis bacteria. People can become infected with tularemia by coming into contact with infected animals or via a tick bite. Symptoms and signs include fever, headache and rash. Tularemia is treated with streptomycin or gentamicin.
Pleural Effusion (Fluid in the Pleural Space)
Pleural effusion is a buildup of fluid in the chest or on the lungs. There are two types of pleural effusion, transudate and exudate. Causes of transudate pleural effusion include congestive heart failure, kidney failure, and cirrhosis. Exudate pleural effusion can be caused by malignancy (cancer) or lung infection. Typically, transudate pleural effusion is more easily treatable. Symptoms of pleural effusion include chest pain, pain when breathing, difficulty breathing, and cough. Treatment depends on the source or cause of the pleural effusion.
Typhus is a disease caused by Rickettsia bacteria. Symptoms and signs include fever, headache, nausea, vomiting, diarrhea, and rash. Antibiotics are recommended as the treatment for endemic and epidemic typhus infections.
Is H. pylori Contagious? Symptoms and Tests
H. pylori (Helicobacter pylori) infection: Is it contagious? H. pylori infection is caused by fecal contamination in either food or water, and by poor hygiene practices such as not washing the hands often. Common symptoms of H. pylori are a discomfort or pain in the area of the stomach. Some individuals describe the pain as gnawing or burning. Treatment of H. pylori infection is antibiotic therapy.
Hailey-Hailey Disease (Familial Benign Pemphigus)
Hailey-Hailey disease (familial benign pemphigus) is a hereditary skin disease that causes painful blistering the skin folds. There is no specific treatment for this disease, and treatment focuses on alleviating symptoms and signs.
Treatment & Diagnosis
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