Secondary Hypertension: Signs, Causes & Treatment
Updated: 2 hours ago
Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: September 2026
Secondary hypertension is high blood pressure caused by another medical condition — such as kidney disease, a hormone disorder, sleep apnea, or a narrowed aorta — rather than arising on its own like primary hypertension. It often has no specific symptoms, but six clues raise suspicion: blood pressure that resists medication, readings over 180/120 mm Hg, sudden onset before age 30 or after 55, no family history, and no obesity. Diagnosis takes 3–6 high readings at separate visits plus tests to find the cause. Treating the underlying condition often lowers or normalizes blood pressure, supported by medications and lifestyle measures.
Quick Answer
Definition: High blood pressure caused by another medical condition — kidneys, arteries, heart, endocrine system, or pregnancy.
Symptoms: Usually no specific symptoms — even at dangerously high levels.
6 warning signs: Resistant hypertension, BP over 180/120, medication that stopped working, sudden onset before 30 or after 55, no family history, no obesity.
14 known causes: Across kidneys (4), hormones (5), and other conditions (5).
Diagnosis: Requires 3–6 high readings at separate appointments plus blood tests, urinalysis, kidney ultrasound, and ECG.
Treatment: Fix the underlying cause with medications or surgery — BP may return to normal; BP drugs and lifestyle changes support control.
Seek care promptly: If BP is over 180/120 mm Hg or no longer responds to medication.
What Is Secondary Hypertension?
Secondary hypertension is high blood pressure that’s caused by another medical condition. It can be caused by conditions that affect the kidneys, arteries, heart, or endocrine system. Secondary hypertension can also occur during pregnancy.
It differs from the usual type of high blood pressure — primary hypertension (also called essential hypertension) — which is what most people mean when they say “high blood pressure.”
The outlook is encouraging: proper treatment of secondary hypertension can often control both the high blood pressure and the condition that causes it. Effective treatment reduces the risk of serious complications — including heart disease, kidney failure, and stroke.
Secondary Hypertension Symptoms: The 6 Warning Signs
Like primary hypertension, secondary hypertension usually has no specific symptoms — even if blood pressure has reached dangerously high levels.
For people already diagnosed with high blood pressure, having any of these signs may mean the condition is secondary hypertension:
Warning Sign | What It Suggests |
Blood pressure that doesn’t respond to blood pressure medications | Known as resistant hypertension |
Very high blood pressure | Systolic over 180 mm Hg or diastolic over 120 mm Hg |
Blood pressure that no longer responds to medication that previously controlled it | Previously controlled BP has changed |
Sudden-onset high blood pressure before age 30 or after age 55 | Age pattern doesn’t match typical primary hypertension |
No family history of high blood pressure | Primary hypertension usually runs in families |
No obesity | A common primary-hypertension driver is absent |
If your blood pressure exceeds 180/120 mm Hg or stops responding to medication you were previously taking, contact a doctor promptly.
Causes: What Can Cause Secondary Hypertension?
Many health conditions can cause secondary hypertension. They fall into three groups.
Kidney Diseases (4 Causes)
Kidney Condition | How It Raises Blood Pressure |
Diabetic nephropathy (diabetes complications) | Diabetes damages the kidneys’ filtering system, leading to high blood pressure |
Polycystic kidney disease | Inherited condition in which cysts interfere with kidney function |
Glomerular disease | The kidneys’ tiny filters (glomeruli) become swollen, which may raise blood pressure |
Renovascular hypertension | Narrowing (stenosis) of one or both kidney arteries; often caused by fatty plaques (atherosclerosis) or fibromuscular dysplasia, in which the artery wall thickens into rings |
Hormone Disorders (5 Causes)
Hormone Condition | How It Raises Blood Pressure |
Cushing syndrome | Caused by corticosteroid medications, a pituitary tumor, or other factors that make the adrenal glands produce too much cortisol |
Aldosteronism | Adrenal glands produce too much aldosterone, making kidneys retain salt and water and lose too much potassium |
Pheochromocytoma | Rare adrenal tumor producing excess adrenaline and noradrenaline; causes long-term high blood pressure or short-term spikes |
Thyroid problems | Both underactive (hypothyroidism) and overactive (hyperthyroidism) thyroid can result in high blood pressure |
Hyperparathyroidism | Excess parathyroid hormone raises blood calcium, triggering a rise in blood pressure |
Other Causes (5)
Other Cause | Details |
Coarctation of the aorta | Present at birth; the body’s main artery is narrowed, forcing the heart to pump harder; blood pressure increases, particularly in the arms |
Sleep apnea | Breathing repeatedly stops and starts during sleep, often with severe snoring; oxygen lack damages blood vessel lining, and an overactive nervous system releases chemicals that raise blood pressure |
Obesity | More body weight means more blood flow and added pressure on artery walls; fat deposits also release chemicals that raise blood pressure |
Pregnancy | Can worsen existing high blood pressure or cause it to develop (pregnancy-induced hypertension or preeclampsia) |
Medications and supplements | Pain relievers, birth control pills, antidepressants, and post-transplant drugs; decongestants and herbal supplements (ginseng, licorice, ephedra/ma-huang); illegal drugs such as cocaine and methamphetamine |
Risk Factors
The greatest risk factor for developing secondary hypertension is simply having a medical condition that can cause high blood pressure — such as kidney, artery, heart, or endocrine system problems.
Complications: Why Untreated Secondary Hypertension Is Dangerous
Secondary hypertension can worsen the underlying medical condition that’s causing the high blood pressure. Without treatment, it can lead to serious health problems:
Complication | What Happens |
Damage to arteries | Hardening and thickening (atherosclerosis), which can lead to a heart attack, stroke, or other complications |
Aneurysm | Blood vessels weaken and bulge; if an aneurysm ruptures, it can be life-threatening |
Heart failure | The heart muscle thickens pumping against higher pressure, eventually struggling to meet the body’s needs |
Weakened and narrowed kidney vessels | Can prevent the kidneys from working properly |
Eye vessel damage | Thickened, narrowed, or torn blood vessels in the eyes can result in vision loss |
Metabolic syndrome | A cluster including increased waist circumference, high triglycerides, low HDL (“good”) cholesterol, high blood pressure, and high insulin; more components mean greater risk of diabetes, heart disease, or stroke |
Memory or thinking trouble | Uncontrolled high blood pressure may affect the ability to think, remember, and learn |
When to See a Doctor
If you have a condition that can cause secondary hypertension, you may need your blood pressure checked more frequently. Ask your health care provider how often to have your blood pressure checked.
How Is Secondary Hypertension Diagnosed?
To diagnose secondary hypertension, a health care provider will take a blood pressure reading using an inflatable cuff.
Importantly, a provider might not diagnose secondary hypertension based on a single high reading. It may take 3 to 6 high blood pressure measurements at separate appointments to confirm the diagnosis. Home blood pressure monitoring and ambulatory blood pressure monitoring — in which a device takes measurements automatically at specific times throughout the day — might make up some of these readings.
Other tests help pinpoint the underlying cause:
Test | What It Checks |
Blood tests | Potassium, sodium, creatinine, blood glucose, total cholesterol, and triglycerides, among others |
Urine test (urinalysis) | Markers that could point to medical conditions that cause high blood pressure |
Kidney ultrasound | Noninvasive imaging; a transducer sends sound waves into the body, and a computer creates images of the kidneys |
Electrocardiogram (ECG or EKG) | Painless test recording the heart’s electrical signals through sensors on the chest and sometimes limbs; helps determine whether a heart problem might be causing the high blood pressure |
Secondary Hypertension Treatment Options
Treatment for secondary hypertension involves treating the medical condition that’s causing it with medications or surgery. Once the condition is treated, blood pressure might decrease or return to normal.
You might still need to continue taking blood pressure medication — and the underlying condition may affect the choice of medication.
Medications: 6 Types
Medication Type | How It Works; Key Notes |
Thiazide diuretics | “Water pills” help kidneys eliminate sodium and water; often the first choice; often generic and less expensive. Side effects: weakness, leg cramps, higher risk of sexual issues. |
Beta blockers | Reduce the heart’s workload and open blood vessels; heart beats slower and with less force. Less effective alone in Black people, but effective combined with a thiazide diuretic. Side effects: fatigue, sleep problems, slowed heart rate, cold hands and feet. Generally not used for people with asthma. |
ACE inhibitors | Relax blood vessels by blocking a chemical that narrows them; especially important with coronary artery disease, heart failure, or kidney failure. Side effects: dizziness, coughing. Should not be taken during pregnancy. |
Angiotensin II receptor blockers (ARBs) | Relax blood vessels by blocking a chemical that narrows them; useful with coronary artery disease, heart failure, or kidney failure; fewer side effects than ACE inhibitors. Should not be used during pregnancy. |
Calcium channel blockers | Relax blood vessel muscles or slow the heart rate; may work better than ACE inhibitors or beta blockers alone for some people. Side effects: water retention, dizziness, constipation. Grapefruit juice interacts with some of these. |
Direct renin inhibitors | Relax and widen arteries by blocking the renin enzyme (example: aliskiren). Side effects: dizziness, diarrhea. People with diabetes or moderate-to-severe kidney problems shouldn’t combine them with ACE inhibitors or ARBs. |
Treatment for secondary hypertension can sometimes be complicated. It might take more than one medication combined with lifestyle changes to control high blood pressure. Your provider may want to see you more often — possibly once a month — until blood pressure is controlled, and may recommend tracking your blood pressure at home.
Self-Care: 7 Lifestyle Measures
Healthy lifestyle changes are recommended to keep the heart healthy and blood pressure low:
Self-Care Measure | Details |
Eat healthy foods | Try the DASH diet (Dietary Approaches to Stop Hypertension) — fruits, vegetables, whole grains, low-fat dairy; plenty of potassium (potatoes, spinach, bananas, apricots); less saturated and total fat |
Decrease salt | 1,500 mg sodium/day is appropriate for people 51+, Black people of any age, and anyone with hypertension, diabetes, or chronic kidney disease; otherwise aim for 2,300 mg/day or less; watch processed foods like canned soups and frozen dinners |
Maintain a healthy weight | Losing even 10 pounds (4.5 kg) can lower blood pressure |
Increase physical activity | At least 30 minutes a day |
Limit alcohol | Up to one drink a day for women, two for men |
Don’t smoke | Tobacco injures blood vessel walls and speeds up artery hardening; ask your provider for help quitting |
Manage stress | Muscle relaxation, deep breathing, and plenty of sleep |
Preparing for Your Appointment
High blood pressure may be discovered during a routine physical. At that point, your primary care provider may order more tests or refer you to a provider who specializes in treating the suspected cause — for example, a nephrologist (kidney specialist) if a kidney problem is suspected.
What You Can Do
Ask about pre-appointment restrictions (for example, restricting your diet for a certain number of hours beforehand)
Write down your symptoms, including any that seem unrelated, and when they began
Write down key personal information, including major stresses or recent life changes
Make a list of all medications, vitamins, and supplements you take, with doses
Write down questions to ask
Questions Worth Asking
What do you think is causing my high blood pressure?
What tests do I need? Do these tests require any special preparation?
Is my high blood pressure temporary or long-lasting?
I have other health conditions — how can I best manage these together?
Are there dietary or activity restrictions I need to follow?
How often do I need to come back to have my blood pressure checked?
Do I need to check my blood pressure at home? How often?
Which type of blood pressure machine is best? Can you help me learn to use it correctly?
Are there brochures or printed material I can have? What websites do you recommend?
What Your Provider Is Likely to Ask
Has anyone in your family ever been diagnosed with high blood pressure? Do you know the reason (for example, diabetes or kidney problems)?
Have you had unusual symptoms?
How much salt is in your diet?
Has your body weight changed recently?
If you were ever pregnant, was your blood pressure higher during pregnancy?
Conclusion: Treat the Cause, Not Just the Number
Secondary hypertension is a different problem from ordinary high blood pressure — and it deserves a different approach. Rather than managing a number in isolation, the goal is to find and treat the underlying condition, which often resolves or dramatically improves the blood pressure itself. Watch for the six warning signs: resistant or suddenly changed blood pressure, very high readings, unusual age of onset, and the absence of typical risk factors like family history or obesity.
If your blood pressure is hard to control, runs over 180/120 mm Hg, or has suddenly changed, talk to your health care provider about whether an underlying cause may be responsible. Ask about testing for kidney, hormone, and sleep-related causes — and start today with the lifestyle measures that support every blood pressure treatment.
Frequently Asked Questions
What is the difference between primary and secondary hypertension?
Primary (essential) hypertension is the usual type of high blood pressure that develops on its own, often related to age, genetics, and lifestyle. Secondary hypertension is high blood pressure caused by another medical condition — such as kidney disease, a hormone disorder, or a narrowed aorta — and can also occur during pregnancy.
What causes secondary hypertension?
Fourteen conditions are known causes, grouped into kidney diseases (diabetic nephropathy, polycystic kidney disease, glomerular disease, renovascular hypertension), hormone disorders (Cushing syndrome, aldosteronism, pheochromocytoma, thyroid problems, hyperparathyroidism), and other causes (coarctation of the aorta, sleep apnea, obesity, pregnancy, medications and supplements).
What are the warning signs of secondary hypertension?
Six signs suggest high blood pressure may be secondary: it doesn’t respond to blood pressure medications (resistant hypertension), it’s very high (over 180/120 mm Hg), it no longer responds to medication that previously controlled it, it starts suddenly before age 30 or after age 55, there’s no family history of high blood pressure, and the person is not obese.
Does secondary hypertension have symptoms?
Like primary hypertension, secondary hypertension usually has no specific symptoms — even at dangerously high levels. That’s why the six warning signs (rather than physical symptoms) are how it’s typically flagged.
How is secondary hypertension diagnosed?
Diagnosis usually requires 3 to 6 high blood pressure readings at separate appointments, possibly including home or ambulatory monitoring. Tests to find the underlying cause include blood tests, urinalysis, kidney ultrasound, and an ECG.
Can secondary hypertension be cured?
In many cases, treating the underlying medical condition with medications or surgery allows blood pressure to decrease or return to normal. You may still need blood pressure medication afterward, depending on the cause.
What blood pressure readings are considered very high?
Blood pressure with a systolic reading over 180 mm Hg or a diastolic reading over 120 mm Hg is considered very high. If your reading reaches this level, contact a health care provider promptly.
What medications treat secondary hypertension?
Six classes are used: thiazide diuretics, beta blockers, ACE inhibitors, angiotensin II receptor blockers (ARBs), calcium channel blockers, and direct renin inhibitors. The underlying condition influences which is chosen, and more than one medication may be needed alongside lifestyle changes.
External References
Secondary hypertension — Symptoms & causes — Symptoms, causes, risk factors, and complications (source updated August 09, 2022)
Secondary hypertension — Diagnosis & treatment — Diagnosis, tests, and treatment options (source updated August 09, 2022)
References
Health information, not medical advice. This article is for general education and is not a substitute for professional diagnosis or treatment. Always consult a qualified healthcare provider about your own health, and seek emergency care for urgent symptoms.
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