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- What is clarithromycin, and how does it work (mechanism of action)?
- What brand names are available for clarithromycin?
- Is clarithromycin available as a generic drug?
- Do I need a prescription for clarithromycin?
- What are the uses for clarithromycin?
- What are the side effects of clarithromycin?
- What is the dosage for clarithromycin?
- Which drugs or supplements interact with clarithromycin?
- Is clarithromycin safe to take if I'm pregnant or breastfeeding?
- What else should I know about clarithromycin?
What is clarithromycin, and how does it work (mechanism of action)?
Clarithromycin is a semi-synthetic macrolide antibiotic chemically related to erythromycin and azithromycin (Zithromax). It is effective against a wide variety of bacteria, such as Haemophilus influenzae, Streptococcus pneumoniae, Mycoplasma pneumoniae, Staphylococcus aureus, and mycobacterium avium, and many others. Like all macrolide antibiotics, clarithromycin prevents bacteria from growing by interfering with their ability to make proteins. Due to the differences in the way proteins are made in bacteria and humans, the macrolide antibiotics do not interfere with production of proteins in humans. The FDA approved clarithromycin in October 1991.
What are the uses for clarithromycin?
Clarithromycin is effective against susceptible bacteria causing the following infections:
It also is used in treating infections caused by mycobacterium avium, a bacterium closely related to the bacterium that causes tuberculosis. Clarithromycin has been used in combination with omeprazole/sodium bicarbonate (Prilosec) in treating H. Pylori that causes stomach ulcers.
What are the side effects of clarithromycin?
Clarithromycin generally is well tolerated, and side effects usually are mild and transient. Common side effects of clarithromycin are:
Other important side effects which are rare, but serious include:
Clarithromycin should be avoided by patients known to be allergic to clarithromycin or other chemically-related macrolide antibiotics, such as erythromycin. Treatment with clarithromycin and other antibiotics can alter the normal bacteria flora of the colon and permit overgrowth of C. difficile, a bacterium responsible for pseudomembranous colitis. Patients who develop pseudomembranous colitis as a result of antibiotics treatment may experience diarrhea, abdominal pain, fever, and sometimes even shock.
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What is the dosage for clarithromycin?
Clarithromycin may be taken with or without food. For most infections the recommended adult dose is 250-500 mg of immediate release tablets twice daily or 1000 mg of extended release tablets once daily for 7-14 days.
Which drugs or supplements interact with clarithromycin?
Clarithromycin interacts with several drugs because it reduces the activity of liver enzymes that breakdown many drugs. This leads to increased blood levels and side effects from the affected drugs. Examples of such interactions include
- olchicine (Colcrys),
- simvastatin (Zocor),
- lovastatin (Mevacor),
- atorvastatin (Lipitor),
- verapamil (Calan),
- amlodipine (Norvasc), and
- diltiazem (Carizem).
Clarithromycin increases blood levels of sildenafil (Viagra, Revatio), tadalafil (Cialis, Adcirca), vardenafil (Levitra), theophylline and carbamazepine (Tegretol), thereby increasing side effects of these drugs.
The occurrence of abnormal heart beats may increase when clarithromycin is combined with drugs that affect heart beat (for example, amiodarone [Coradone], quinidine [Quinidine Gluconate, Quinidine Sulfate], and disopyramide).
Is clarithromycin safe to take if I'm pregnant or breastfeeding?
Clarithromycin is excreted in breast milk.
What else should I know about clarithromycin?
What preparations of clarithromycin are available?
Tablets (immediate or extended release): 250 and 500 mg. Suspension: 125 or 250 mg per 5 ml (teaspoonful).
How should I keep clarithromycin stored?
Tablets and suspension should be stored at room temperature 15 -30 C (59-86 F) in a tightly closed container. The oral suspension should not be refrigerated after mixing and should be used within 14 days.
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Clarithromycin (Biaxin, Biaxin XL) is an antibiotic drug prescribed for the treatment of a large variety of bacterium. Clarithromycin is used to treat infections of the middle ear, tonsils, throat, larynx, bronchioles, lungs, and skin. Side effects, drug interactions, warnings and precautions, and pregnancy safety information should be reviewed prior to taking any medication.
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Related Disease Conditions
Sinus Infection (Sinusitis)
Sinus infection (sinusitis) is caused by allergies, infection, and chemicals or other irritants of sinuses. Signs and symptoms are headache, fever, and facial tenderness, pressure, or pain. Treatments of sinus infections are generally with antibiotics and at times, home remedies.
Swimmer's Ear (External Otitis)
Swimmer's ear (external otitis) is an infection of the skin that covers the outer ear canal. Causes of swimmer's ear include excessive water exposure that leads to trapped bacteria in the ear canal. Symptoms of simmer's include a feeling of fullness in the ear, itching, and ear pain. Chronic swimmer's ear may be caused by eczema, seborrhea, fungus, chronic irritation, and other conditions. Common treatment includes antibiotic ear drops.
Tonsil stones are small clusters of calcifications that form when food, dead cells, mucus, and bacteria get stuck in the nooks and crannies of the tonsils. Tonsil stones are hard, appear as white or yellowish formations on the tonsils, and usually smell bad due to bacteria. If symptoms occur, they may include persistent bad breath, sore throat, difficulty swallowing, ear pain, and cough.
Middle Ear Infection (Otitis Media)
Middle ear infection (otitis media) is inflammation of the middle ear. There are two forms of this type of ear infection, acute and chronic. Acute otitis media is generally short in duration, and chronic otitis media generally lasts several weeks. Babies, toddlers, and children with a middle ear infection may be irritable, pull and tug at their ears, and experience numerous other symptoms and signs. Treatment depends upon the type of ear infection.
Tonsillitis is a contagious infection with symptoms of bad breath, snoring, congestion, headache, hoarseness, laryngitis, and coughing up blood. Tonsillitis can be caused acute infection of the tonsils, and several types of bacteria or viruses (for example, strep throat or mononucleosis). There are two types of tonsillitis, acute and chronic. Acute tonsillitis lasts from one to two weeks while chronic tonsillitis can last from months to years. Treatment of tonsillitis and adenoids include antibiotics, over-the-counter medications, and home remedies to relieve pain and inflammation, for example, salt water gargle, slippery elm throat lozenges, sipping warm beverages and eating frozen foods (ice cream, popsicles), serrapeptase, papain, and andrographism Some people with chronic tonsillitis may need surgery (tonsillectomy or adenoidectomy).
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.
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.
Pneumonia is inflammation of the lungs caused by fungi, bacteria, or viruses. Symptoms and signs include cough, fever, shortness of breath, and chills. Antibiotics treat pneumonia, and the choice of the antibiotic depends upon the cause of the infection.
Laryngitis is an inflammation of the voice box (vocal cords). The most common cause of acute laryngitis is infection, which inflames the vocal cords. Symptoms may vary from degree of laryngitis and age of the person (laryngitis in infants and children is more commonly caused by croup). Common symptoms include a "barky" cough, a hoarse cough, fever, cold, runny nose, dry cough, and loss of voice. Chronic laryngitis generally lasts more than three weeks. Causes other than infection include smoking, excess coughing, GERD, and more. Treatment depends on the cause of laryngitis.
Bronchitis is inflammation of the airways in the lung. Acute bronchitis is short in duration (10-20 days) in comparison with chronic bronchitis, which lasts for months to years. Causes of acute bronchitis include viruses and bacteria, which means it can be contagious. Acute bronchitis caused by environmental factors such as pollution or cigarette smoke is not contagious. Common symptoms for acute bronchitis include nasal congestion, cough, headache, sore throat, muscle aches, and fatigue. Acute bronchitis in children also my include runny nose, fever, and chest pain. Treatment for acute bronchitis are OTC pain relievers, cough suppressants (although not recommended in children), and rest. Infrequently antibiotics may be prescribed to treat acute bronchitis.
Strep throat is a bacterial infection of the throat. Signs and symptoms of strep throat include headache, nausea, vomiting, sore throat, and fever. Strep throat symptoms in infants and children are different than in adults. Strep throat is contagious and is generally passed from person-to-person. Treatment for strep throat symptoms include home remedies and OTC medication; however, the only cure for strep throat are antibiotics.
Is H. pylori Contagious?
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.
Whooping Cough (Pertussis)
Whooping cough (pertussis) is highly contagious respiratory infection that is caused by the bacteria Bordetella pertussis. There are an estimated 300,000 plus deaths annually from whooping cough (pertussis). Whooping cough commonly affects infants and young children but can be prevented with immunization with the vaccine. First stage whooping cough symptoms are a runny nose, sneezing, low-grade fever, a mild cough with the cough gradually becoming more severe. After one to two weeks, the second stage of whooping cough begins.
Scarlet Fever (Scarlatina)
Scarlet fever, a bacterial infection caused by group A Streptococcus bacteria, causes symptoms and signs such as fever, rash with a sandpaper-like texture, and sore throat. Oral penicillin is the standard treatment for scarlet fever, or scarlatina.
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.
Nontuberculous Mycobacterial Lung Disease (NTM, Symptoms, Treatment, Side Effects)
Nontuberculous mycobacteria (NTM), most commonly, M. avium complex or MAC, is a mycobacteria that causes lung infections and disease. Nontuberculous mycobacteria are commonly found in soil, air, and water. Examples of how NTM lung infection are transmitted include swimming, using a hot tub (NTM bacteria are aerosolized), or playing with or handling soil. The most common symptoms of NTM lung infection are chronic, dry cough, and shortness of breath. Sometimes the cough may have mucous or blood. Other symptoms of NTM lung disease include fatigue, chest pain, malaise, and weakness. As NTM lung disease progresses, fevers, night sweats, and appetite loss may occur. Treatment guidelines for NTM lung disease depend upon the type and extent of the infection, and the person's health.
Legionellosis is an infection caused by the Legionella pneumophila bacterium. There are two forms of legionellosis: Pontiac fever and Legionnaires' disease, which is the more severe of the two infections. Symptoms of Pontiac fever include fever, headache, muscle aches, and chills. Symptoms of Legionnaires' disease include cough, chills, fever and sometimes muscle aches, headaches, loss of appetite, diarrhea, and severe pneumonia. While Pontiac fever resolves on its own, Legionnaires' disease must be treated with antibiotics.
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