Diarrhea, headache, nausea, vomiting, and abnormal taste may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly. Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. Tell your doctor right away if you have any serious side effects, including: muscle weakness, signs of liver disease (such as nausea/vomiting that doesn't stop, yellowing eyes/skin, dark urine), easy bruising/bleeding, mental/mood changes (such as agitation, confusion), signs of lupus (such as rash on nose and cheeks, new or worsening joint pain), signs of kidney problems (such as change in the amount of urine, pink/bloody urine). Get medical help right away if you have any very serious side effects, including: severe dizziness, fainting, fast/irregular heartbeat. This medication may rarely cause a severe intestinal condition due to a bacteria called C. difficile. This condition may occur during treatment or weeks to months after treatment has stopped. Tell your doctor right away if you develop: diarrhea that doesn't stop, abdominal or stomach pain/cramping, blood/mucus in your stool. If you have these symptoms, do not use anti-diarrhea or opioid products because they may make symptoms worse. Use of this medication for prolonged or repeated periods may result in oral thrush or a new yeast infection. Contact your doctor if you notice white patches in your mouth, a change in vaginal discharge, or other new symptoms. A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: fever, swollen lymph nodes, rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing. Amoxicillin can commonly cause a mild rash that is usually not serious. However, you may not be able to tell it apart from a rare rash that could be a sign of a severe allergic reaction. Get medical help right away if you develop any rash. This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist. In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch. In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
A product that may interact with this drug is: methotrexate. Many drugs besides clarithromycin may affect the heart rhythm (QT prolongation), including amiodarone, disopyramide, dofetilide, pacritinib, pimozide, procainamide, quinidine, sotalol, among others. Other medications can affect the removal of clarithromycin from your body, which may affect how clarithromycin works. Examples include rifamycins (such as rifabutin), efavirenz, nevirapine, among others. Clarithromycin can slow down the removal of other medications from your body, which may affect how they work. Examples of affected drugs include colchicine, digoxin, some drugs used to treat erectile dysfunction-ED/pulmonary hypertension (such as sildenafil, tadalafil), ergot alkaloids (such as ergotamine, dihydroergotamine), flibanserin, some statin drugs (such as lovastatin, simvastatin), tamsulosin, tolvaptan, ticagrelor, among others. Some products need stomach acid so that the body can absorb them properly. Lansoprazole decreases stomach acid, so it may change how well these other products work. Some affected products include atazanavir, erlotinib, levoketoconazole, nelfinavir, pazopanib, rilpivirine, sparsentan, certain azole antifungals (itraconazole, ketoconazole, posaconazole), among others. Before using lansoprazole, consult your doctor or pharmacist about the other medications you take and for advice on how to reduce or avoid these types of interactions. Lansoprazole is very similar to dexlansoprazole. Do not use medications containing dexlansoprazole while using lansoprazole. This medication may interfere with certain lab tests (such as urine glucose test), possibly causing false test results. Make sure lab personnel and all your doctors know you use this drug.