If you will be taking this medicine for a long time, it is very important that your doctor check you at regular visits for any problems or unwanted effects that may be caused by this medicine.
This medicine can cause a change in the heart rhythm called prolongation of the QT interval. This condition may change the way your heart beats and can cause palpitations or fainting spells. Check with your doctor right away if you start having any of these symptoms.
Do not use ranolazine if you are using carbamazepine (Tegretol®), clarithromycin (Biaxin®), nefazodone (Serzone®), phenobarbital, phenytoin (Dilantin®), rifabutin (Mycobutin®), rifampin (Rifadin®, Rimactane®), rifapentin (Priftin®), medicine to treat fungus infections (such as itraconazole, ketoconazole, Nizoral®, or Sporanox®), medicine to treat HIV or AIDS (such as indinavir, nelfinavir, ritonavir, saquinavir, Crixivan®, Fortovase®, Invirase®, Norvir®, or Viracept®), or St. John's wort.
Do not use this medicine to treat a sudden onset of chest pain.
This medicine may cause some people to become dizzy, lightheaded, drowsy, or less alert than they are normally. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy or not alert.
Grapefruit and grapefruit juice may increase the effects of ranolazine by increasing the amount of medicine in the body. You should not eat grapefruit or drink grapefruit juice while you are taking this medicine.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.