Clarithromycin (previously known by it's brand name Biaxin) is an antibiotic that's used to treat a variety of bacterial infections in adults and children. It's available as a generic immediate-release tablet and solution taken twice per day and an extended-release tablet taken once per day. Side effects include a metallic or sour taste, nausea, vomiting, and diarrhea.
Lung infections related to on-going bronchitis in adults
Pneumonia in adults and children
Sinus infections in adults and children
Strep throat in adults and children
Tonsil infections in adults and children
Skin infections in adults and children
Ear infections in children
Treatment and prevention of certain infections in adults with HIV
Tablets only: Stomach ulcers caused by Helicobacter pylori (H. pylori) in adults
Clarithromycin is a macrolide antibiotic. It works by stopping bacteria from making certain proteins inside their cells. This causes the bacteria to not be able to grow and survive.
Source: DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Rare
Fever with or without chills
itching, skin rash
severe stomach cramps and pain
stomach tenderness
unusual bleeding or bruising
vomiting
watery and severe diarrhea, which may also be bloody
yellow eyes or skin
Incidence not known
black, tarry stools
blistering, peeling, or loosening of the skin
blurred vision
chest pain or discomfort
clay-colored stools
confusion about identity, place, and time
cool, pale skin
dark urine
difficulty with swallowing
dizziness
fainting
fast, slow, pounding, or irregular heartbeat or pulse
feeling of unreality
feeling that others are watching you or controlling your behavior
feeling that others can hear your thoughts
feeling, seeing, or hearing things that are not there
increased hunger
joint or muscle pain
light-colored stools
loss of appetite
nightmares
puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
recurrent fainting
red skin lesions, often with a purple center
red, irritated eyes
redness, swelling, or soreness of the tongue
seizures
sense of detachment from self or body
severe mood or mental changes
shakiness
skin eruptions
slurred speech
sores, ulcers, or white spots in the mouth or on the lips
stomach pain
swollen glands
tightness in the chest
unpleasant breath odor
unusual behavior
unusual tiredness or weakness
vomiting of blood
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Less common
Belching
bloated or full feeling
change in sensation of taste
excess air or gas in the stomach or bowels
headache
indigestion
mild diarrhea
passing gas
Incidence not known
Change in sense of smell
continuing ringing or buzzing or other unexplained noise in the ears
feeling of constant movement of self or surroundings
hearing loss
lightheadedness
loss of taste
mood or mental changes
sensation of spinning
shakiness in the legs, arms, hands, or feet
sore mouth or tongue
swelling or inflammation of the mouth
tongue discoloration
tooth discoloration
trouble sleeping
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Treats many types of infections
Available as a extended-release tablet, immediate-release tablet, and a liquid
Available as a lower-cost generic
Can cause changes in taste, diarrhea, and stomach upset
Has many drug interactions
Not the best option if you have kidney problems
Not safe during pregnancy
You can take clarithromycin immediate-release tablet or clarithromycin oral suspension with or without food. If it's upsetting your stomach, taking it with food could help.
Take clarithromycin extended-release tablet with food. Make sure to swallow it whole. Don't crush, chew, or break the tablet.
Take clarithromycin exactly as prescribed. Make sure to finish the entire treatment course, even if you're feeling better. Stopping the medication earlier than prescribed can make your infection come back and become harder to treat.
If you develop watery or bloody diarrhea, fever, fatigue, or stomach cramps anytime during treatment or after stopping clarithromycin, seek medical help right away because these could be signs of C. difficile-related diarrhea, which needs to be treated right away.
Clarithromycin can leave a metallic or sour taste in your mouth, but this should get better and eventually go away when you stop taking the medication.
If you experience diarrhea from taking clarithromycin, let your provider know. If they think the diarrhea isn't too serious, they might recommend that you take a probiotic to help lessen this side effect. If so, make sure to separate the probiotic from clarithromycin by at least 2 hours to prevent clarithromycin from killing the "good" bacteria in the probiotic.
Clarithromycin interacts with a lot of commonly-used medications. Make sure to tell your provider about all of the medications you're taking before and during treatment with clarithromycin.
More tips for the oral suspension (liquid)
The clarithromycin suspension is available as 125 mg/5 mL and 250 mg/5 mL strengths. Make sure you know which strength of the suspension you have to ensure you're taking the correct dose.
Shake the bottle well before measuring out the clarithromycin suspension. Make sure to only use a medication dose cup or syringe from the pharmacy to measure out your dose. Don't use household spoons because they aren't accurate and might cause you to take the wrong dose.
Store the clarithromycin suspension at room temperature, don't put it in the refrigerator.
The clarithromycin suspension can be stored for up to 14 days after you receive it from the pharmacy. After 14 days, throw away the bottle, even if it still has medication in it.
Clarithromycin can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Severe allergic reactions to clarithromycin are possible, including life-threatening reactions like facial swelling and anaphylaxis (e.g., closing of the throat). Let your provider know if you have an allergy to antibiotics. If you notice hives, rash, red skin, swelling of the lips or tongue, or difficulty breathing after taking clarithromycin, get medical attention right away.
Additionally, although rare, clarithromycin can cause serious skin reactions, such as Stevens-Johnson syndrome (SJS) and Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS). If you notice changes in your skin, such as rash, blisters, skin reddening, or skin peeling, stop using clarithromycin and get medical attention right away.
Though rare, some people who took clarithromycin reported serious liver problems, including liver failure. Get medical attention right away if you notice swelling of your stomach, stomach pain, yellowing of your skin or the whites of your eyes, stool changes (clay-colored stools), nausea, vomiting, confusion, or dark or brown urine. You might need to stop using the medication to prevent further liver damage.
Taking clarithromycin with certain medications can give you serious side effects. Make sure to tell your provider about all of the medications you're taking, especially if you take colchicine (Colcrys, Mitigare), Juxtapid (lomitapide), a statin, certain diabetes medications (e.g., insulin, sulfonylureas, meglitinides), quetiapine (Seroquel), oral blood thinners, or benzodiazepines (e.g., alprazolam (Xanax). Don't start any new medications while taking clarithromycin without asking your provider or pharmacist first to make sure the combination is safe to take.
Risk factors: Older adults | Low blood potassium or magnesium levels | Kidney problems | Heart rate or heart rhythms problems | Taking other medications that can cause QT prolongation
Clarithromycin can affect your heart rhythm, which can be serious and life-threatening. One example includes lengthening the time period from when the heart pumps and then relaxes. This is known as QT prolongation. Your risk for QT prolongation is higher if you have certain factors, including abnormal electrolyte levels, heart rhythm problems, or are taking other medications that cause heart rhythm problems, such as amiodarone (Pacerone), among others. If you feel your chest pounding, have trouble breathing, have chest pain, or feel faint or lightheaded while taking clarithromycin, call 911 right away.
Risk factors: Blood vessel-related heart problems
Though very rare, some studies have reported that people with blood vessel-related heart disease who take clarithromycin are at a higher risk of death from heart problems compared to people who take other antibiotics. While the connection is unclear, your provider will weigh the risks and benefits of this medication for you, especially if you have heart problems. Speak to your provider if you have any concerns.
Although rare, clarithromycin can raise your risk of getting infected with a bacteria called Clostridioides difficile (C. diff), which can cause severe diarrhea. Antibiotics change the amount of normal bacteria in your stomach and intestines. This can cause C. diff to overgrow in your gut and lead to an infection. It's important to recognize the difference between diarrhea as a side effect of clarithromycin and this type of infectious diarrhea. C. diff-related diarrhea can cause rapid heart rate, foul-smelling diarrhea, fever, nausea, frequent bowel movements (even up to 15 times per day) and is an emergency. If you have any of these symptoms, get medical attention right away so you can get tested for C. diff infection and receive treatment.
If you have myasthenia gravis, taking clarithromycin can worsen symptoms like muscle weakness and difficulty breathing. Ask your provider about safer antibiotics if you have myasthenia gravis.
Your provider will prescribe a dose based on the type of infection you have, how severe it is, if you have kidney problems, and if you're taking a medication that interacts with clarithromycin.
Clarithromycin immediate-release tablet and clarithromycin suspension:
Adults
Bronchitis: The typical dose is 250 mg to 500 mg by mouth every 12 hours for 7 to 14 days.
Sinus infection: The typical dose is 500 mg by mouth every 12 hours for 14 days.
Pneumonia: The typical dose is 250 mg by mouth every 12 hours for 7 to 14 days.
Strep throat and tonsil infection: The typical dose is 250 mg by mouth every 12 hours for 10 days.
Skin infection: The typical dose is 250 mg by mouth every 12 hours for 7 to 14 days.
Treatment and prevention of infections in people with HIV: The typical dose is 500 mg by mouth every 12 hours.
H. pylori infection (in combination with other medications): The typical dose is 500 mg by mouth every 8 to 12 hours for 10 to 14 days.
Children: Your child's provider will determine the dose based on their body weight. The typical dose is 7.5 mg/kg (up to the adult dose) by mouth every 12 hours for 10 days.
Clarithromycin extended-release tablet:
Bronchitis and pneumonia (adults only): The typical dose is 1 gram by mouth once daily for 7 days.
Sinus infections (adults only): The typical dose is 1 gram by mouth once daily for 14 days.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Severe allergy to macrolide antibiotics
Severe liver problems associated with previous use of clarithromycin
Taking pimozide, lovastatin, simvastatin (Zocor), Juxtapid (lomitapide), lurasidone (Latuda), or ergot derivatives (e.g., migraine medications)
Taking colchicine (Colcrys, Mitigare) and have renal or liver problems
Lung infections related to on-going bronchitis in adults
Pneumonia in adults and children
Sinus infections in adults and children
Strep throat in adults and children
Tonsil infections in adults and children
Skin infections in adults and children
Ear infections in children
Treatment and prevention of certain infections in adults with HIV
Tablets only: Stomach ulcers caused by Helicobacter pylori (H. pylori) in adults
Sudden worsening of chronic obstructive pulmonary disease (COPD) from a bacterial infection
Skin infections (e.g., cellulitis)
Urethra or cervix infections
Ear infections (ages 6 months and older)
Pneumonia (ages 6 months and older)
Strep throat (ages 2 years and older)
Tonsil infections (ages 2 years and older)
Respiratory infections (including upper respiratory tract infection and lower respiratory tract infection)
Listeria infection
Diphtheria infection
Intestinal amebiasis
Sexually-transmitted infections, STIs (e.g., chlamydia, gonorrhea, syphilis)
Prevention of rheumatic fever
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