Introduction
High blood pressure (Hypertension) is known as the "silent killer" because it can go undiagnosed till it causes fatal complications. It affects about one out of every three adult Americans over twenty years of age, with approximately 40 million clinic visits a year and close to 2,000 deaths a month. Treatment of high blood pressure poses a continuing challenge. Lifestyle changes and drugs that lower the blood pressure form the mainstay of treatment. Sometimes, drug therapy may involve more than one agent, in diverse combinations and dosage forms. Captopril-HCTZ (Captopril-Hydrochlorthiazide, Capozide) is one such combination. It contains two antihypertensive agents, Captopril and Hydrochlorthiazide, in a single dosage tablet form.
How Captopril-Hydrochlorthiazide Works
Captopril is in a class of drugs called ACE-inhibitors or Angiotensin converting enzyme inhibitors.it blocks the activation of angiotensin in the blood. Activated angiotensin narrows the blood vessels and indirectly causes the retention of salts and fluid by the kidneys. These actions of angiotensin raise blood pressure. By blocking the activation of angiotensin, Captopril indirectly lowers blood pressure.
HydroChlorthiazide (also called HCTZ) is a diuretic, acting on the kidney to encourage salt and water loss by inhibiting salt reabsorption by the kidneys. This reduces fluid load and blood volume, reducing blood pressure in the process. It works best with salt restriction in the diet. Thus, the two agents--captopril and hydrochlorthiazide--work in synergy to reduce blood pressure.
How Captopril-HCTZ is Used
Captopril-HCTZ is used as a first line drug or second line drug after either one of its components has been used alone. It is conveniently taken once a day and comes in several different dosage combinations, allowing for shuffling of doses to meet individual needs.
Captopril-HCTZ is particularly advantageous in cases where Hypertension co-exists with other complications or disease states, like previous 'stroke' patients, Coronary artery disease and Diabetes mellitus where it has been shown to reduce the likelihood of further complications.
The combination still leaves room for addition of other antihypertensive agents, like Beta-Blockers or Calcium channel blockers, in very difficult or treatment resistant cases of hypertension.
