Diuretic Drugs – what’re the best?

In the Heart Foundation consultation, the question was recently asked what advantages the dehydrating agent chlortalidone has over HCT (hydrochlorothiazide), which is prescribed much more frequently in this country? The more uniform effect of chlortalidone is not the only difference, as the following expert answer emphasizes.

Irbesartan/hydrochlorothiazide

The consultation question in wording:

In the Heart Foundation brochure “Hypertension: What to do?” Prof. Eschenhagen noted on page 34 that the dehydrating agent chlortalidone is a better drug than hydrochlorothiazide. What are the advantages of the drug chlortalidone in terms of effect or side effect? Why should it be better? I would be grateful for any information, as my cardiologist may want to change my medication. He is also very interested in the information. (Bert R., Sigmaringen)
Expert answer:

Chlortalidone and HCT (hydrochlorothiazide) are both diuretic drugs from the group of so-called thiazide diuretics and act very similarly. Both lower blood pressure and are part of the standard therapy for high blood pressure.

Chlortalidone has two advantages: First, it has been tested successfully in large studies involving thousands of patients. This includes the largest and most important independently conducted blood pressure studies such as ALLHAT and SPRINT. In contrast, HCT has only been studied in smaller trials.

Chlortalidone

When many studies are pooled, chlortalidone versus HCT reduces the relative risk of cardiovascular complications by 21% (Roush GC et al, Hypertension 2012). Nevertheless, HCT is used much more frequently than chlortalidone in Germany due to tradition or habit, which can be viewed quite critically.
Effect of chlortalidone more uniform

Second, chlortalidone has a significantly longer half-life in the body. This means that the effect lasts longer and is more uniform than that of HCT. Thus, chlortalidone is also “forgiving” of the occasional forgetting to take a tablet.

As with HCT, the standard dose of chlortalidone is 1 x 12.5-50 mg/day (usually 1 x 25 mg/day).

Regarding your question about side effects: It is impossible to predict which drug you will tolerate better. This is something you and your doctor will have to try out.

High Blood Pressure Symptoms

Most people with hypertension don’t exhibit any high blood pressure signs or symptoms. Usually, it takes several years for the condition to cause noticeable problems. People who do have symptoms may experience headache, dizziness, and blurred vision. Unfortunately, many people don’t seek medical care until they have severe symptoms related to organ damage.

Signs and Symptoms of High Blood Pressure: An Overview

Most people with high blood pressure (also known as hypertension) don’t have any high blood pressure symptoms or signs. This is because high blood pressure doesn’t cause problems over a day or weeks — or even months. It usually takes several years for the condition to cause noticeable symptoms, and even when it does cause problems, the symptoms are often mild and nonspecific (meaning they could be caused by several different conditions).   For this reason, high blood pressure is often referred to as “the silent killer.” People with the condition typically don’t even realize they have it until they have blood pressure readings that are too high.  

Possible High Blood Pressure Symptoms

In some cases, however, a person can have signs or symptoms of high blood pressure. These include:  

  • Headache
  • Dizziness
  • Blurred vision
  • Nausea.  

However, many people don’t seek medical care until they have more severe symptoms from the organ damage that long-term (chronic) high blood pressure can cause.  

Malignant High Blood Pressure and Its Symptoms

About 1 percent of people with high blood pressure do not seek medical care until their symptoms are quite severe. Severe high blood pressure is referred to as malignant hypertension. In malignant hypertension, the diastolic blood pressure (the bottom number of a blood pressure reading) often exceeds 140 mmHg. People with malignant high blood pressure symptoms may experience:  

When high blood pressure becomes this severe, emergency hospitalization and lowering of blood pressure are required to prevent brain bleeding or stroke.

Causes of High Blood Pressure

In most cases, there are no specific causes of high blood pressure. Factors such as being overweight, smoking, and having diabetes can increase a person’s risk of developing this condition, but they are not “causes” in and of themselves. High blood pressure without an identifiable cause is known as primary or “essential hypertension.”

Understanding What Causes High Blood Pressure

In most people, a single, specific cause of high blood pressure is not known. This is called primary or essential hypertension. In other people, high blood pressure is the result of another medical problem or medicine. When the cause is known, this is called secondary high blood pressure.  

high blood pressure

If a person is diagnosed with high blood pressure, it doesn’t mean that he or she is “too nervous,” overanxious, or obsessive. This is a popular myth. High blood pressure is not nervous tension. In fact, many people who are perfectly calm have high blood pressure.  

Primary Hypertension — When There Is No Known Cause

For nine out of ten people, there is no identifiable cause of high blood pressure. This is called “primary hypertension” or “essential hypertension.” Most people with primary hypertension don’t even realize that they have it; the majority of people with the condition feel no different from those who have normal blood pressure. That’s why high blood pressure is often called “the silent killer.”  

Secondary Hypertension

In one out of ten people, the high blood pressure cause is known. This is called secondary hypertension. Some conditions that can cause secondary hypertension include:  

High Blood Pressure Cause Versus Risk Factors

While not specific causes of high blood pressure, certain traits can increase a person’s chance of developing it. These factors are known as high blood pressure risk factors and include:  

  • Having diabetes
  • Being a male over the age of 45 or a female over the age of 55
  • Being overweight
  • Eating a lot of salty foods (see Salt and High Blood Pressure)
  • Being of African-American descent.  

Although more men have high blood pressure than women, women do increase their risk of the disease if they take birth control pills.  

What Makes High Blood Pressure Worse?

High blood pressure can be made worse by different things. A few factors that can worsen the disease include: