Enalapril: Background, Use and Dosage

Enalapril is a drug belonging to the ACE inhibitor group used worldwide to treat high blood pressure and other cardiovascular diseases. It is discussed in this article.
Enalapril: Background, Use and Dosage

Last update: 03 April, 2023

Cardiovascular diseases have a high incidence and are the leading cause of death worldwide, according to data from the World Health Organization. Therefore, it isn’t surprising that there are a large number of drugs available to treat them, enalapril being one of the most used.

Of all cardiac pathologies, arterial hypertension is one of the most frequent. It’s a chronic disease characterized by higher-than-normal blood pressure figures. This increase causes serious damage to organs such as the heart, brain, and kidneys.

In the human body there are various mechanisms that can raise or lower blood pressure when necessary. Some drugs such as enalapril intervene in these processes, helping the body to return to normal.

What is enalapril?

Enalapril is an angiotensin-converting enzyme (ACE) inhibitor drug, so it disrupts the renin-angiotensin-aldosterone system. In this way, it can be used to treat high blood pressure and different heart conditions.

The administration of the compound is carried out orally or intravenously, depending on the patient’s requirements. This medicine has a capacity of oral absorption of 60% in its inactive form. Once inside the body, hepatic hydrolysis occurs and it’s transformed into its active ingredient called enalaprilat.

This drug is fast-acting. It has been shown that oral administration can reduce blood pressure by 15-20% after 6-8 hours.

What is the medicine for?

This medication is used to treat high blood pressure. In this sense, it’s recommended in patients who suffer from this pathology or who are at risk of suffering from it due to other concomitant conditions. At a renal level, it’s able to increase blood supply and improve diuresis, that is, the production of urine.

Long-term treatment with enalapril helps reduce peripheral vascular resistance, improving circulation. It does this by dilating the blood vessels, without altering the heart rate. In addition, its prolonged use also helps to stop ventricular hypertrophy in hypertensive patients.

Finally, the drug is administered to patients with congestive heart failure in order to lower blood pressure and improve their lifestyle. It has even been shown that only 15.6% of patients with heart failure and treated with enalapril have required hospitalization.

Hypertensive man in medical consultation is prescribed enalapril.
Enalapril is one of the most prescribed medications for the control of arterial hypertension, both in men and women.

How does enalapril work in the body?

One of the mechanisms that the human body has to increase blood pressure is the renin-angiotensin-aldosterone system. Through the angiotensin converting enzyme (ACE) the organism transforms angiotensin I into angiotensin II, which will stimulate the secretion of aldosterone in the adrenal gland.

Aldosterone will act at the renal level to increase sodium and water retention, thus increasing blood pressure. Enalapril and all ACE inhibitors prevent the transformation of angiotensin I into angiotensin II, inhibiting the corresponding enzyme.

In this way, there’ll be no production of aldosterone, so the blood pressure won’t increase. This drug also acts on other substrates such as bradykinin, increasing its concentration in the blood. The increase in bradykinin will stimulate the production of nitric oxide and prostaglandins, leading to peripheral vasodilation.

When and how should it be ingested?

The intake of enalapril in any of its presentations must be carried out under strict medical prescription. Currently, there’s no single recommended dose, so the amount of milligrams needed will vary depending on the patient’s condition.

In general terms, to treat high blood pressure , a daily dose is necessary that will range from 2.5 to 20 milligrams, reaching a maximum of 40 milligrams daily.

When it’s used to treat other cardiovascular diseases, it’s administered together with other drugs. According to the internal leaflet, the initial dose will be 2.5 milligrams and will be increased gradually in the following weeks. The intake is usually divided into two doses per day to obtain better results.

Enalapril side effects

Adverse effects generated by enalapril are infrequent and when they appear they do not limit daily activities. In this sense, among the side reactions that can develop are the following:

Some people may be allergic to this compound. Treatment should be discontinued immediately. The most noticeable symptoms of a drug allergy are shortness of breath, itching, and swelling of the mouth, throat, and extremities.

On the other hand, if extreme weakness, fainting, or blackouts occur at any time during use, a doctor should be consulted. The person may be taking a higher dose than required, and adjustment will be necessary.

Hypertensive pregnant women can't take enalapril.
Pregnant women cannot use enalapril, since it’s contraindicated for them.

Warnings and contraindications of enalapril

The administration of enalapril is contraindicated in patients allergic to the compound or to other ACE inhibitors. Furthermore, its use isn’t recommended in patients who are more than 3 months pregnant or who have a history of angioedema.

It’s important to notify the doctor if other drugs are ingested, especially those aimed at lowering blood pressure. This is in order to avoid interactions between the compounds. The specialist should also be notified in the following cases:

  • A recent kidney transplant or some pathology that affects the kidney
  • When suffering from diabetes mellitus
  • If medicines are being taken to treat gout or arrhythmias
  • If potassium or lithium supplements are ingested

Continuous checking is necessary

Enalapril is used to treat various chronic cardiovascular conditions. It’s important to note that these pathologies don’t have a cure. However, the use of drugs helps to prevent the progression of the disease and improve symptoms.

In this sense, it will be necessary to have a continuous medical check-up and comply with the treatment. In this way it’s possible to improve the patient’s lifestyle and increase their life expectancy, despite the existing medical condition.

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