II. Indications
- Conditions
- Community Acquired Pneumonia
- Limit to suspected Mycoplasma pneumonia or Legionella pneumonia
- Macrolide resistant pneumococcus is common
- Consider Doxycycline as alternative
- Streptococcal Pharyngitis
- Macrolides are only indicated in significant allergy to beta-lactams
- Non-tuberculous Mycobacterial infections
- Helicobacter infections
- Community Acquired Pneumonia
- Activity
- Macrolide resistance is increasing
- Resistance to one Macrolide is resistance to all
- Spectrum includes organisms covered by Erythromycin
- Streptococcus Pneumoniae (Pneumococcus)
- Staphylococcus aureus
- Toxoplasmosis gondii
- Mycobacterium leprae
- Mycobacterium Avium Complex
- Borrelia Burgdorferi
- Macrolide resistance is increasing
III. Medications
- Tablets: 250 and 500 mg
- Suspension: 125 and 250 mg/5 ml
IV. Dosing
- See Pertussis
- May take with or without food
-
General
- Adult: 250 to 500 mg orally twice daily
- Child: 7.5 mg/kg orally twice daily
-
Group A Streptococcal Pharyngitis (second line agent in beta lactam allergy)
- Adult: Take 250 mg orally twice daily for 10 days
- Child: 7.5 mg orally twice daily for 10 days
-
Acute Exacerbation of Chronic Bronchitis
- Adult: Take 250 mg orally twice daily for 7 to 14 days
-
Mycobacterium Avium Complex Disease (e.g. AIDS)
- Adult: 500 mg orally twice daily
- Active disease is treated with at least 2 drugs
-
Renal Dosing
- eGFR 30 to 60 ml/min: Decrease dose by 50%
- eGFR <30 ml/min: Decrease dose by 75%
V. Pharmacokinetics
- Half Life: 5 hours
VI. Adverse Effects
- See Macrolide
- Dysgeusia or Distorted Taste (20%)
- Calcium Channel Blocker Drug Interaction (see below)
- Myasthenia Gravis (risk of exacerbation)
-
QT Prolongation
- Appears to be a class effect of Macrolides, but seen more with Azithromycin
- Higher risk with known QTc Prolongation, Hypokalemia, Hypomagnesemia, Class IA or III Antiarrhythmics
- Increased cardiovascular deaths
- Observation in some studies as of 2018, but needs confirmation
- Inghammer (2017) Am J Epidemiol +PMID:29155931 [PubMed]
- Svanström (2014) BMJ 349:g4930 +PMID:25139799 [PubMed]
VII. Safety
- Considered safe in Lactation
- Pregnancy Category C
- Clarithromycin is considered a potential Teratogen (Cleft Lip association)
- Macrolides in general may increase heart defects with first trimester exposure of 5-7 days
- Fan (2020) BMJ 368: m331 +PMID:32075790 [PubMed]
VIII. Drug Interactions
- Clarithromycin is a strong CYP3A4 inhibitor
- Includes Calcium Channel Blockers as below
- Numerous interactions including Carbamazepine, Quetiapine, Simvastatin
- Toxicity risks with Ergotamines and Colchicine
-
Warfarin
- May increase INR
-
Calcium Channel Blockers
- Clarithromycin increases Calcium Channel Blocker levels via CYP3A4 inhibition
- Highest risk with Dihydropyridine Calcium Channel Blockers (Nifedipine, Felodipine)
- Highest risk in age over 65 years old
- Provokes Hypotension and Bradycardia
- Risk of Acute Kidney Injury (often requiring hospitalization)
- Number needed to harm: 1 in 465 for over age 65 years
- References
IX. Resources
- Clarithromycin Tablet (DailyMed)
Images: Related links to external sites (from Bing)
Related Studies
| clarithromycin (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing) | ||
| CLARITHROMYCIN 125 MG/5 ML SUS | Generic | $0.86 per ml |
| CLARITHROMYCIN 250 MG TABLET | Generic | $0.47 each |
| CLARITHROMYCIN 250 MG/5 ML SUS | Generic | $1.43 per ml |
| CLARITHROMYCIN 500 MG TABLET | Generic | $0.41 each |
| CLARITHROMYCIN ER 500 MG TAB | Generic | $4.32 each |