Do not take Karvezide if you are allergic (hypersensitive) to irbesartan and hydrochlorothiazide, or any of the other ingredients of Karvezide or to medicines chemically related to sulfonamide (ask your doctor or pharmacist for further clarification) during the last 6 months of pregnancy, see section Pregnancy and breastfeeding if you are breast-feeding if you have severe liver or kidney problems if you have difficulty in producing urine if you have a condition which is associated with persistently high calcium or low potassium levels in your blood