Hello there, Your target blood pressure will depend on many other factors like whether you have diabetes or any kidney related trouble. I think anywhere less than 140 systolic (upper limit) and less than 90 diastolic (lower limit) is good for you if no other problems are there. Olmesartan is normally given in the dose of 20 mg and can be uptitrated upto 40 mg and like you have already found, going above 40mg does not have much benefit. You can probably take Olmesartan 20 H and take it twice a day. However you need to review with your physician about this and get some tests of kidney and electrolytes done regularly if you are increasing the dose of Hydrochlorothiazide. Continue to use less salt and include some form of exercise in your daily routine if your heart condition allows. This helps to further reduce BP. Take care.