Chronic Conditions · Hypertension · Blood Pressure
What Is High Blood Pressure? A Complete Guide to Hypertension in the UK
Medically authored & reviewed by
Dr Abdishakur M Ali
General Practitioner · Telehealth Expert · Clinical Director
Last reviewed: March 2026
GPhC Registered Pharmacy
✓ GPhC-registered pharmacy #9011198·✓ Pharmacist independent prescribers·✓ Discreet next-day delivery·✓ UK-regulated online consultation
Medical disclaimer: This article is for informational purposes only. Our prescribers are GPhC-registered pharmacist independent prescribers. Always consult a qualified healthcare professional about your blood pressure management.
High blood pressure — also known as hypertension — is one of the most common chronic conditions in the UK. The British Heart Foundation estimates that as many as 5 million adults in the UK have undiagnosed high blood pressure, and millions more manage it with medication. Left untreated, hypertension causes progressive, silent damage to the heart, kidneys, brain, and blood vessels — dramatically increasing the risk of stroke, heart attack, and other life-threatening conditions. This guide explains what high blood pressure is, its causes, complications, and the full range of treatment options available.
Manage Your Blood Pressure Online
Access Doctor provides prescription blood pressure medications following a GPhC-regulated online consultation. Our pharmacist independent prescribers will assess your suitability.
Start Consultation →✓ GPhC-registered pharmacy #9011198 ✓ Pharmacist independent prescribers ✓ Discreet next-day deliveryUnderstanding Blood Pressure: What the Numbers Mean
Blood pressure is measured in millimetres of mercury (mmHg) and recorded as two numbers — for example, 120/80 mmHg:
- Systolic pressure (top number) — the pressure in your arteries when your heart beats and pumps blood out
- Diastolic pressure (bottom number) — the pressure in your arteries between heartbeats when the heart is at rest
| Category | Reading | Action Required |
|---|---|---|
| Optimal | Below 120/80 | Maintain healthy lifestyle |
| Normal | 120–129 / 80–84 | Monitor regularly |
| High-normal | 130–139 / 85–89 | Lifestyle changes recommended |
| Stage 1 Hypertension | 140–159 / 90–99 | Medication typically recommended with lifestyle changes |
| Stage 2 Hypertension | 160+ / 100+ | Medication usually required; medical review needed |
| Hypertensive crisis | 180+ / 120+ | Seek immediate medical attention |
Silent killer: Most people with high blood pressure have no symptoms. This is why regular blood pressure checks are so important. The NHS offers free blood pressure checks at GP surgeries, some pharmacies, and through home monitoring devices.
What Causes High Blood Pressure?
Primary (Essential) Hypertension — 90–95% of Cases
Primary hypertension has no single identifiable cause. It develops gradually over many years through a combination of:
- Genetic predisposition — a family history of hypertension significantly increases your risk
- Physical changes with ageing — arteries become stiffer over time, increasing resistance to blood flow
- Unhealthy lifestyle factors — high salt intake, obesity, physical inactivity, excessive alcohol, smoking
Secondary Hypertension — 5–10% of Cases
Secondary hypertension has a specific underlying cause. Common causes include:
- Chronic kidney disease — the most common secondary cause; impaired kidneys fail to regulate fluid and salt balance properly
- Obstructive sleep apnoea — repeated nocturnal oxygen desaturation activates the sympathetic nervous system
- Thyroid disorders (both underactive and overactive thyroid)
- Primary hyperaldosteronism (excess aldosterone production by the adrenal glands)
- Congenital heart defects
- Certain medications — NSAIDs, oral contraceptives, decongestants, stimulants, and some herbal remedies
Complications of Untreated High Blood Pressure
Uncontrolled hypertension causes progressive damage to the vascular system and vital organs. The higher and longer-lasting the raised blood pressure, the greater the risk of:
- Stroke — high blood pressure is the single most important risk factor for stroke in the UK
- Heart attack (myocardial infarction) — coronary artery damage from hypertension significantly raises heart attack risk
- Heart failure — the heart works harder against increased resistance, eventually weakening
- Chronic kidney disease — hypertension damages the delicate blood vessels in the kidneys
- Vascular dementia — sustained high blood pressure damages small blood vessels in the brain
- Aortic aneurysm — weakening and bulging of the main artery in the chest or abdomen
- Peripheral arterial disease — narrowing of arteries to the legs, causing pain and mobility problems
Lifestyle Changes to Lower High Blood Pressure
Lifestyle modification is first-line treatment for all stages of hypertension and can significantly reduce blood pressure — sometimes enough to avoid or delay medication:
| Lifestyle Change | Expected BP Reduction | Notes |
|---|---|---|
| Reduce salt intake to <6g/day | 2–8 mmHg | Avoid processed foods, which contain most dietary salt |
| DASH or Mediterranean diet | 3–11 mmHg | Rich in fruits, vegetables, whole grains, low-fat dairy |
| Regular aerobic exercise (30 min/day) | 4–9 mmHg | Brisk walking, swimming, cycling — 150 mins per week |
| Achieve healthy weight | 1 mmHg per kg lost | 5–10kg weight loss can produce meaningful BP reduction |
| Limit alcohol (<14 units/week) | 2–4 mmHg | More than 14 units/week significantly raises BP |
| Stop smoking | Variable | Smoking raises acute BP and cardiovascular risk dramatically |
| Stress management | 2–5 mmHg | Yoga, meditation, breathing exercises, regular sleep |
Medications to Treat High Blood Pressure
When lifestyle changes are insufficient, or when cardiovascular risk is high, NICE recommends antihypertensive medication. The main classes available include:
| Drug Class | Examples | How They Work | Common First-Line Use |
|---|---|---|---|
| ACE inhibitors | Ramipril, lisinopril, perindopril, enalapril | Block angiotensin-converting enzyme; prevent blood vessel constriction | First-line for most people under 55 |
| ARBs | Candesartan, losartan, valsartan, irbesartan | Block angiotensin II receptors; relax blood vessels | Alternative to ACE inhibitors; better tolerated by some |
| Calcium channel blockers | Amlodipine, felodipine, nifedipine | Prevent calcium entering heart muscle and vessel walls; cause vasodilation | First-line for people over 55; good for black British patients |
| Diuretics | Indapamide, bendroflumethiazide | Remove excess sodium and fluid via kidneys; reduce blood volume | Third-line addition or if other agents insufficient |
| Beta-blockers | Bisoprolol, atenolol | Reduce heart rate and force of contraction | Not routinely first-line; used when other agents inappropriate |
NICE BP targets (NG136): For most adults, the treatment target is below 140/90 mmHg (clinic reading) or 135/85 on home monitoring. For people aged 80 and over, the target is below 150/90 mmHg. For people with diabetes or established cardiovascular disease, more ambitious targets may apply.
Monitoring Your Blood Pressure at Home
Home blood pressure monitoring (HBPM) is recommended by NICE for confirming a diagnosis of hypertension and for monitoring treatment response. To measure blood pressure accurately at home:
1
Rest: Sit quietly for 5 minutes before measuring.
2
Posture: Sit with your back supported, feet flat on the floor, arm at heart level.
3
Measure twice: Take two measurements, one minute apart. Use the average.
4
Record results: Record readings morning and evening for at least 4 days (ideally 7 days).
5
Share with your prescriber: Share your home readings at your next consultation — they are more representative than a single clinic reading.
Access Blood Pressure Treatments Online
Access Doctor provides prescription blood pressure medications including amlodipine, lisinopril, ramipril, and more. GPhC-registered pharmacy, pharmacist independent prescribers, discreet delivery.
View Blood Pressure Treatments →✓ GPhC-registered pharmacy #9011198 ✓ Pharmacist independent prescribers ✓ Discreet next-day deliveryFrequently Asked Questions
What is a normal blood pressure reading?
A normal blood pressure reading is below 120/80 mmHg. The upper number (systolic) measures pressure when the heart beats; the lower (diastolic) measures pressure between beats. High blood pressure (hypertension) is diagnosed when readings consistently reach 140/90 mmHg or above, or 135/85 mmHg on home monitoring.
What are the symptoms of high blood pressure?
High blood pressure is often called the ‘silent killer’ because most people have no obvious symptoms even when readings are dangerously elevated. When symptoms do occur, they may include severe headaches, blurred vision, nosebleeds, and chest pain. These usually only appear in very high readings or during a hypertensive crisis and require urgent medical attention.
What causes high blood pressure?
Primary (essential) hypertension — which has no single identifiable cause — accounts for 90–95% of cases and develops gradually over years. Secondary hypertension has a specific underlying cause such as kidney disease, sleep apnoea, thyroid problems, or certain medications. Lifestyle factors including obesity, excessive salt intake, alcohol, smoking, and sedentary behaviour all contribute.
How is high blood pressure treated?
Treatment depends on the severity of hypertension and cardiovascular risk. Lifestyle changes (healthy diet, exercise, weight loss, reducing salt and alcohol, quitting smoking) are first-line for all patients. Medication — including ACE inhibitors, angiotensin receptor blockers, calcium channel blockers, diuretics, or beta-blockers — is added when lifestyle changes are insufficient or risk is high.
What complications can untreated high blood pressure cause?
Untreated hypertension is a major risk factor for stroke, heart attack, heart failure, kidney disease, vascular dementia, aortic aneurysm, and peripheral arterial disease. The British Heart Foundation estimates that 5 million adults in the UK have undiagnosed high blood pressure.
Can I get blood pressure medication online in the UK?
Yes. Access Doctor provides access to blood pressure medications including amlodipine, lisinopril, ramipril, and bendroflumethiazide following a GPhC-regulated online consultation with our pharmacist independent prescribers. Existing patients managing stable hypertension may be able to access repeat prescriptions online.
References
- NICE. Hypertension in adults: diagnosis and management (NG136). Updated 2023. nice.org.uk/guidance/ng136
- NHS. High blood pressure (hypertension). nhs.uk/conditions/high-blood-pressure-hypertension
- British Heart Foundation. High blood pressure. bhf.org.uk
- Kitt J et al. New approaches in hypertension management: a review. Curr Hypertens Rep. 2019. pubmed.ncbi.nlm.nih.gov
Access Doctor is a GPhC-registered online pharmacy (registration number 9011198). All prescriptions are issued by GPhC-registered pharmacist independent prescribers. Medicines are MHRA-compliant UK-licensed products.