High blood pressure (hypertension) commonly affects one-third of the UK population. It is estimated that more than 5.5 mln people in the UK live with undiagnosed high blood pressure (GOV.UK, 2017). High blood pressure (BP) increases the risk of heart attack, stroke and other long-term health conditions when left untreated. This post focuses on high blood pressure treatment. The main drugs used in the treatment will be reviewed according to NICE guidelines and prescribing popularity in the UK.
High Blood Pressure: Initiation of the Treatment
High blood pressure treatment is commenced when patients have clinical blood pressure (measured by GP) of :
- 140/90mmHg or higher or
- The average results of ambulatory blood pressure monitoring (blood pressure taken at home during 24 hours) are 135/85 mmHg or higher.
- A patient has a 10-year cardiovascular risk of over 10% (risk estimation for a cardiovascular event such as heart attack) or target-organ damage, for example, chronic kidney disease or diabetes.
Patients with a clinical high blood pressure of 160/100 mmHg or higher or average home blood pressure of 150/95 mmHg or higher will be treated regardless of any other risks or concomitant conditions.
High Blood Pressure: What is the Recommended Treatment?
Treatment of high blood pressure is managed in a stepwise manner (BNF, 2019). The selection of the initial drug for the treatment of high blood pressure depends on the age of the patient and the ethnicity. When one medicine fails to reduce the blood pressure to a satisfactory level, patients need to take two or more drugs to control their blood pressure.
The main classes of drugs used in the UK in the treatment of high blood pressure include:
- ACE inhibitors with Ramipril being most commonly prescribed
- Angiotensin-2-receptor antagonists, with Losartan being the most popular
- Calcium channel blockers with Amlodipine being the most frequently prescribed
- Diuretics with Bendroflumethiazide being most popular
Depending on individuals’ age and ethnicity, in the first instance, one would be expected to take an ACE inhibitor such as Ramipril or Calcium channel blocker such as Amlodipine when high blood pressure is diagnosed.
High blood pressure treatment of patients under 55 years of age
Patients under 55 years of age diagnosed with high blood pressure are offered an ACE inhibitor.
The most commonly prescribed ACE inhibitor in the UK is Ramipril. In 2018, Ramipril was one of the most widely prescribed drugs in the UK, with over 28 mln items specified. Other popular ACE inhibitors used in the treatment of high BP include (according to popularity):
The whole list of ACE inhibitors includes over 10 drugs that are licensed for high blood pressure treatment.
If ACE inhibitor is not tolerated or contra-indicated angiotensin-2-receptor antagonist commonly known as angiotensin-2-blocker (ARBs) is offered.
The most common angiotensin-2-receptor blocker prescribed in the UK is Losartan.
Other drugs in this class used in the management of high blood pressure in the UK include:
If both ACE inhibitor and angiotensin-2-receptor blocker are not tolerated, a beta-blocker is considered, for example, bisoprolol or atenolol. Although effective in reducing blood pressure, beta-blockers are not commonly used to treat hypertension.
Step 2 of high blood pressure management in those aged 55 and under includes a combination treatment involving two drugs:
ACE inhibitor (e.g. Ramipril) or angiotensin-II receptor antagonist (e.g. Losartan) with calcium channel blocker (e.g. Amlodipine).
The most familiar calcium channel blocker used in the UK is Amlodipine. Like Ramipril, Amlodipine is one of the most commonly prescribed drugs in the UK and the most commonly used Calcium channel blocker. Other calcium channel blockers include:
In 2018, Amlodipine was the most commonly prescribed high blood pressure medication, overtaking Ramipril just by over 1 mln items (29 mln items in total).
If calcium channel blocker is not tolerated, a diuretic is offered, for example, Indapamide. Diuretics are commonly known as water tablets.
Triple therapy involves:
- ACE inhibitor (e.g Ramipril) or angiotensin-2-blocker (e.g. Losartan) + 2. calcium channel blocker (e.g. Amlodipine) + 3. diuretic (e.g. Indapamide)
High blood pressure: treatment of patients over 55 years of age or patients who are of Caribbean or African origin
Calcium channel blocker is offered, for example, Amlodipine. If calcium channel blocker is not tolerated, a diuretic is provided, for instance, Indapamide or chlorthalidone.
Combination therapy of Calcium channel blocker (Amlodipine) or a diuretic (Indapamide) with ACE inhibitor (Ramipril) or angiotensin-II blocker (Losartan) is offered.
Treatment as with patients under 55 years of age.
High blood pressure: an overview of the main classes of drugs
To read more about all medicines mentioned in this post, including a complete list of possible side effects, visit medicines.org.uk, where you can access product information leaflets for any UK-licensed medication.
High blood pressure drugs: ACE inhibitors
- Most commonly prescribed: Ramipril and lisinopril.
- Mechanism of action: cause widening of the blood vessels and consequently reduction of blood pressure
- It is recommended that the first dose of ACE inhibitor is taken at night
- It is recommended that patients have blood checks during the treatment to monitor renal (kidney) function and electrolyte balance
Common side effects:
- Headaches, dizziness
- Tickling, dry cough which does not go away
- Abdominal discomfort, dyspepsia, diarrhoea, nausea, vomiting
High blood pressure drugs: Calcium channel blockers
- Most commonly prescribed drug: Amlodipine
- Mechanism of action: as the name suggests, this group of drugs block calcium entry, which is needed for muscle contraction, consequently causing dilation of blood vessels
Common side effects:
- Drowsiness, dizziness, headaches (widespread at the start of the treatment
- Nausea, abdominal pain
- Ankle swelling, oedema (accumulation of fluid in tissues of the body)
High blood pressure drugs: Angiotensin-2-blockers
- Most commonly prescribed drug: Losartan
- Mechanism of action: dilation of blood vessels.
Common side effects:
- Hyperkalaemia (low level of potassium)
- Abdominal pain, nausea, and vomiting
High blood pressure medication: Diuretics
- Most commonly prescribed: bendroflumethiazide (no longer recommended as the first-line diuretic in the treatment of hypertension). Instead, Indapamide and chlortalidone should be used
- Mechanism of action: promote urine output (commonly known as water tablets) which lowers the blood volume and consequently reduces blood pressure
Common side effects:
- Constipation, diarrhoea
High blood pressure: lifestyle modifications
Modifiable factors contributing to high blood pressure:
- Lack of exercise
- Lousy diet (high alcohol and salt consumption)
Making changes to an unhealthy lifestyle is the most crucial factor to consider to reduce blood pressure. Exercise and a balanced diet can be as effective in lowering blood pressure as drug treatment.