Clarithromycin and Lansoprazole interaction
Clarithromycin and Lansoprazole: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Lansoprazole (Prevacid) label · effective 2025-07-08
For information about contraindications of antibacterial agents (clarithromycin and amoxicillin) indicated in combination with PREVACID or PREVACID SoluTab, refer to the Contraindications section of their prescribing information.
Combination Therapy with Clarithromycin and Amoxicillin Clinical Impact: Concomitant administration of clarithromycin with other drugs can lead to serious adverse reactions, including potentially fatal arrhythmias, and are contraindicated.
For more information specific to antibacterial agents (clarithromycin and amoxicillin) indicated for use in combination with PREVACID or PREVACID SoluTab, refer to Warnings and Precautions section of their prescribing information.
Intervention: See Contraindications and Warnings and Precautions in prescribing information for clarithromycin.
CYP2C19 or CYP3A4 Inhibitors Clinical Impact: Increased exposure of lansoprazole is expected when used concomitantly with strong inhibitors [see Clinical Pharmacology (12.3) ] .
From the Clarithromycin label · effective 2026-01-01
Proton Pump Inhibitors: Omeprazole No Dose Adjustment Omeprazole: The mean 24-hour gastric pH value was 5.2 when omeprazole was administered alone and 5.7 when coadministered with clarithromycin as a result of increased omeprazole exposures [see Pharmacokinetics ( 12.3 )] (see also Omeprazole under “Drugs That Affect Clarithromycin Tablets” in the table below).
Saquinavir (in patients with normal renal function) Ritonavir (in patients with normal renal function) No Dose Adjustment Proton Pump Inhibitors: Omeprazole Use With Caution Omeprazole: Clarithromycin concentrations in the gastric tissue and mucus were also increased by concomitant administration of omeprazole [see Pharmacokinetics ( 12.3 )] .
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.