Brenda,   Thanks for your question.   Renexa (generic - ranolazine) is a drug that is prescribed for chronic angina which is chest pain caused by coronary artery disease (blockages).  The drug has varying effectiveness depending on the study reviewed.   The major side effects of Renexa are dizziness, headache, nausea, and constipation.  Many of the symptoms are dose related which means that the higher the dose, the greater the chance of developing symptoms.  However, if you are experiencing any new symptoms, you should check with your physician as this could also be a side effect of this drug.    Dosing of Renexa ranges from 500 mg once a day to 1000mg twice a day.   I hope this has been helpful.   Martin Cane, M.D.