What special precautions should I follow?  

Before taking clarithromycin,

• tell your doctor and pharmacist if you are allergic to clarithromycin, azithromycin (Zithromax), dirithromycin (Dynabac) (not available in the U.S.), erythromycin (E.E.S., E-Mycin, Erythrocin), telithromycin (Ketek), or any other medications
• tell your doctor if you are taking astemizole (Hismanal) (not available in the U.S.), cisapride (Propulsid), dihydroergotamine (DHE 45, Migranal), ergotamine (Ergomar, in Cafergot, in Migergot), pimozide (Orap), or terfenadine (Seldane) (not available in the U.S.). Your doctor may tell you not to take clarithromycin if you are taking one or more of these medications.
• tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: anticoagulants ('blood thinners') such as warfarin (Coumadin); alfentanil (Alfenta); alprazolam (Xanax); bromocriptine (Parlodel); carbamazepine (Tegretol); cholesterol-lowering medications such as lovastatin (Mevacor) and simvastatin (Zocor); cilostazol (Pletal); colchicine; cyclosporine (Neoral, Sandimmune); darifenacin (Enablex); digoxin (Lanoxin); erlotinib (Tarceva); eszopiclone (Lunesta); fluconazole (Diflucan); certain medications for HIV such as nelfinavir (Viracept), ritonavir (Norvir), and ziodvudine (AZT, Retrovir); certain medications for irregular heartbeat such as disopyramide (Norpace) and quinidine; methylprednisolone (Medrol), midazolam (Versed); omeprazole (Prilosec); phenytoin (Dilantin); ranitidine (Zantac); rifabutin (Mycobutin); rifampin (Rifadin, Rimactane); sildenafil (Viagra), tacrolimus (Prograf); theophylline (Theo-Dur); triazolam (Halcion); valproate (Depacon) and valproic acid (Depakote). Many other medications may also interact with clarithromycin, so tell your doctor about all the medications you are taking, even those that do not appear on this list. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
• tell your doctor if you have or have ever had kidney or liver disease .
• tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking clarithromycin, call your doctor.

What special dietary instructions should I follow?  

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?  

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.