Hi thanks for your question. Your father is having chronic renal disease (CRD) and is on dialysis 3 times a week. patient with CRD needs lot of medicine to maintain normal function of body. The list of medicine you have posted on HCM are important for his health. Here I will give you brief description of these drugs. Niacin is vitamin B3 along with vitaminB12 very important for general well being of patient B3 promotes promotes general blood vessels and circulatory health. Plavix is clopidogrel bisulfate is platlet inhibator along with aspirin doesn’t allow clot formation. Renevela is Sevelamer carbonate belongs to group of medication called phosphate binder.Phosphate is made of phosphorus ,which is very important component of normal bone and cell metabolism.In CRD kidneys cannot retain phosphorus ,so it has to be supplemented. Synthyroid is thyroid hormone, he might be hypothyroid, so thyroid hormone has to be given. Hydralazine is vasodilator used for control of blood pressure and prevention of stroke and kidneys problems. Isosorbide dinitrite is venodilator and is necessary for control of his blood supply to his heart, it prevents angina.(Pain due to decrease blood supply to heart). Paricalcitor is oral activated vitamin D3 used for prevention and treatment of secondary hyperthyroidism asoociated with CRD. Carvedilol belong to group of drugs called beta blockers,helps in control of blood pressure and circulation of heart. Simvastatin is hypolipidermic drug used for weight loss along with diet and exercise,Increased lipid impairs the circulation of the blood. Clonidine is used for control of blood pressure. Controlloing blood pressure in CRD is very difficult; patient has to be put on more than one drug. Hope this answers your question.