Clarithromycin (macrolide, antibiotic)

Clarithromycin is a macrolide antibiotic. It works by stopping the growth of bacteria.

This antibiotic treats only bacterial infections. It will not work for viral infections (such as common cold, flu). Unnecessary use or misuse of any antibiotic can lead to its decreased effectiveness and potential drug resistance.

Know the basics

What is clarithromycin used for?

• Respiratory tract infections
• Skin and soft tissue infections
• Mycobacterium avium complex infections
• Helicobacter pylori-associated peptic ulcer disease (PUD)

How should I take clarithromycin?

Read the directions on the packaging for complete information. Check the label and expiration date.

For oral dosage forms, swallow it whole without chewing, crushing, or dissolving it in liquid. Oral suspensions need to be reconstituted with an appropriate amount of water. Only use a medical-grade measuring cup for each dose, not a household spoon.

For parenteral dosage forms, only a licensed healthcare professional should administer it.

How do I store clarithromycin?

Store this product at room temperature away from direct light and moisture. After reconstitution, do not refrigerate it. Use it within 14 days. To prevent drug damage, you should not store it in the bathroom or the freezer. 

There may be different brands of this drug that may have different storage needs. So, it is important to always check the product package for instructions on storage, or ask your pharmacist. For safety, you should keep all medicines away from children and pets.

You should not flush this product down the toilet or pour them into a drain unless instructed to do so. Additionally, it is important to properly discard this product when it is expired or no longer needed. Consult your pharmacist for more details about how to safely discard your product.

Know the precautions & warnings

What should I know before using clarithromycin?

Before using this drug, tell your doctor if you are/have:

• Pregnant or breastfeeding.
• Taking any other medicines. This includes any prescription, OTC, and herbal remedies.
• An allergy to any of the ingredients of this product.
• Any other illnesses, disorders, or medical conditions.

Is it safe to take clarithromycin during pregnancy or breast-feeding?

Unfortunately, there isn’t enough information about the safety of using this drug during pregnancy and breastfeeding. Please always consult with your doctor to weigh the potential benefits and risks before taking any medication.

This medication is pregnancy risk category C according to the US Food and Drug Administration (FDA).

FDA pregnancy risk category reference below:

• A= No risk
• B= No risk in some studies
• C= There may be some risk
• D= Positive evidence of risk
• X= Contraindicated
• N= Unknown

Know the side effects

What are the side effects of clarithromycin?

Like all drugs, this product may have side effects. If they occur, side effects are generally mild and resolve once treatment is finished or the dose is lowered. Some reported side effects include:

• Headache
• Insomnia
• Skin rash
• GI disturbances
• Nausea, vomiting
• Diarrhea
• Increased risk of opportunistic infections
• Increased BUN

However, not everyone experiences these side effects. In addition, some people may experience other side effects. So, if you have any concerns about a side effect, please consult your doctor or pharmacist.

Know the interactions

What drugs may interact with clarithromycin?

This medication may interact with other drugs that you are currently taking, which can change how your drug works or increase your risk for serious side effects. 

To avoid any potential drug interactions, you should keep a list of all the drugs you are using (including prescription drugs, nonprescription drugs, and herbal products) and share it with your doctor and pharmacist. 

Drugs with known interactions:

• CYP3A4 inducers
• Antihyperglycemic agents
• Warfarin
• Etravirine
• Azole antifungals
• Digoxin
• Quinidine
• Zidovudine
• Ritonavir
• Calcium-channel blockers
• Triazolam

Potentially fatal drug interactions with:

• Cisapride
• Pimozide
• Domperidone
• Terfenadine
• Astemizole
• Ergotamine, dihydroergotamine
• Midazolam
• Lomitapide
• Statins
• Colchicine
• Ticagrelor

If you experience an adverse drug interaction, inform your doctor immediately to reevaluate your treatment plan. Approaches include dose adjustment, drug substitution, or ending therapy.

Does food or alcohol interact with clarithromycin?

This drug may interact with food or alcohol by altering the way the drug works or increase the risk for serious side effects. Please discuss with your doctor or pharmacist any potential food or alcohol interactions before using this drug.

What health conditions may interact with clarithromycin?

This drug may interact with underlying conditions. This interaction may worsen your health condition or alter the way the drug works. Therefore, it is important to always let your doctor and pharmacist know all the health conditions you currently have, especially:

• Cholestatic jaundice
• Arrhythmias
• Heart disease
• Liver disease
• Kidney impairment
• Porphyria
• Chronic diarrhea
• Myasthenia gravis
• Hypomagnesemia (low magnesium)

Understand the dosage

The information provided is not a substitute for any medical advice. Therefore, you should always consult with your doctor or pharmacist before using any medication.

What is the dose for an adult?

Tonsillitis/Pharyngitis

Take 250 mg of clarithromycin every 12 hours for 10 days

Sinusitis

Take 500 mg orally every 12 hours for 14 days

For extended-release, take 1000 mg orally every 24 hours for 14 days

Bronchitis

Immediate-release:

• H. influenzae: 500 mg orally every 12 hours for 7 to 14 days
• H. parainfluenzae: 500 mg orally every 12 hours for 7 days
• M. catarrhalis or S. pneumoniae: 250 mg orally every 12 hours for 7 to 14 days

Extended-release: 1000 mg orally every 24 hours for 7 days

Pneumonia

Immediate-release:

• H. influenzae: 250 mg orally every 12 hours for 7 days
• S. pneumoniae or Chlamydophila pneumoniae: 250 mg orally every 12 hours for 7 to 14 days

Extended-release: 1000 mg orally every 24 hours for 7 days

Mycoplasma Pneumonia

Immediate-release: 250 mg orally every 12 hours for 7 to 14 days

Extended-release: 1000 mg orally every 24 hours for 7 days

Skin and Structure Infection

Immediate-release: 250 mg orally every 12 hours for 7 to 14 days

What is the dose for a child?

Tonsillitis/Pharyngitis

Immediate-release: 6 months or older: 7.5 mg/kg orally every 12 hours for 10 days

Sinusitis

Immediate-release: 6 months or older: 7.5 mg/kg orally every 12 hours for 10 days

Mycoplasma Pneumonia

Immediate-release: 6 months or older: 7.5 mg/kg orally every 12 hours for 10 days

Pneumonia

Immediate-release: 6 months or older: 7.5 mg/kg orally every 12 hours for 10 days

Otitis Media

Immediate-release: 6 months or older: 7.5 mg/kg orally every 12 hours for 10 days

Skin and Structure Infection

Immediate-release: 6 months or older: 7.5 mg/kg orally every 12 hours for 10 days

Mycobacterium avium-intracellulare Prophylaxis

Immediate-release: 20 months or older: 7.5 mg/kg orally twice a day

Maximum dose: 500 mg/dose

How is clarithromycin available?

Clarithromycin is available in the following dosage forms and strengths:

• Tablet: 250 mg, 500 mg
• Extended-release tablet: 500 mg
• Oral suspension: 125 mg/5 mL, 250 mg/5 mL

What should I do in case of an emergency or overdose?

In case of an emergency or an overdose, call your local emergency services or go to the nearest emergency room.

What should I do if I miss a dose?

If you miss a dose, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and take your regular dose as scheduled. Do not take a double dose. Avoid missing doses to prevent antimicrobial resistance and treatment failure.