Hypertension
Overview

Hypertension is blood pressure that is too high. In some children, hypertension can be a serious condition. It can increase the risk of getting other diseases, especially if the hypertension continues into their adult years.
This information covers:
- what hypertension is and why it is important
- symptoms of hypertension
- what may cause hypertension
- how your doctor can find out if your child has hypertension
- any treatment or lifestyle changes that your child may need
- monitoring hypertension
- long-term effects of hypertension.
About blood pressure
Blood pressure is the force, or pressure, caused mainly by the heart pumping, that makes the blood flow round the body. It is important that blood pressure is in a healthy range – not too high and not too low.
Symptoms
- headaches that keep coming back or that do not go away
- vomiting (being sick), especially with a headache
- blurred (fuzzy) vision
- odd feelings/numbness
- poor coordination, or movement disorders – they may seem clumsy
- temporary weakness or paralysis (difficulty moving) of one side of the face
- seizures (which may also be called fits or convulsions).
If your child has any of the above, take them to your doctor to check their blood pressure as soon as possible.
Causes
Hypertension in children is rare. It is much more common in adults, especially older adults.
In children it is often caused by an underlying heath condition.
Tests and diagnosis
Your child’s doctor or nurse will measure your child’s blood pressure a few times before diagnosing (identifying) hypertension. Your doctor or nurse will know the healthy range of blood pressure for your child.
More about tests and diagnosis
Treatment
If your child continues to have hypertension after careful assessment and monitoring, he or she will need to control their blood pressure.
Eating a healthy diet with no added salt and getting plenty of exercise can help to reduce blood pressure. Some children need to take medicines.
About the future
Hypertension can be a serious condition if it is not well controlled. Hypertension increases the risk of other diseases, especially if it continues into adulthood. These include stroke, heart attack, heart failure and kidney disease.
If your child continues to have hypertension, his or her blood pressure will need to be carefully controlled. If your child has an underlying condition, this may need treatment.
Follow up
Contact your doctor straight away if your child is vomiting (being sick) and cannot take their medicine for more than 24 hours (1 day).
Symptoms
What are the symptoms of hypertension?
Often, there are no early symptoms in hypertension, especially if it is mild or moderate.
More common symptoms
Some children with hypertension have the following symptoms:
- headaches that keep coming back or that do not go away
- vomiting (being sick), especially with a headache
- blurred (fuzzy) vision.
If your child has any of the above symptoms, take them to your doctor to check their blood pressure as soon as possible.
Less common symptoms
A few children with hypertension – especially if it is very high (malignant hypertension) – have the following symptoms:
- blurred (fuzzy) vision
- odd feelings/numbness
- poor coordination, or movement disorders – they may seem clumsy
- temporary weakness or paralysis (difficulty moving) of one side of the face (this is called Bell’s palsy)
- seizures (which may also be called fits or convulsions).
If your child has any of the above symptoms, take them to your doctor or call 999 straight away.
Causes
Your child’s doctor will try to find out what is causing hypertension in your child, and how severe it is. Hypertension may be primary or secondary. It may also be considered malignant.
Primary hypertension
Secondary hypertension
Sometimes an underlying problem with the kidneys or another part of the body is causing the hypertension. This is called secondary hypertension. It is more common in children. It can be acute (sudden) or long-term.
Acute hypertension
Acute hypertension starts suddenly or gets worse quickly. If your child has acute hypertension, he or she is admitted to the hospital. Your doctor will try to diagnose and treat the condition that is causing the high blood pressure. In some cases, after treatment, the blood pressure gets better over time.
Causes of acute hypertension in children include:
- structural problems in the urinary system – where one or more parts have not developed normally
- pyelonephritis – infection in the kidney
- glomerulonephritis – a group of diseases that affect the kidney filters, the glomeruli
- a side-effect of some medicines
- occasionally, problems with the endocrine system (which controls many of the body’s functions), the heart or brain.
Structural problems of the urinary system
In some children, one or more parts of the urinary system do not develop, or grow, normally. Children with structural problems are usually born with them, and they are sometimes found on a pregnancy ultrasound scan.
Different problems in the urinary system may cause acute hypertension:
-
Posterior urethral valves - a blockage in the back part of the urethra (nearest the bladder) in some
boys
- pelviureteric junction (PUJ) dysfunction – a blockage between the kidney and the ureter
- Vesicoureteric reflux and Reflux nephropathy some urine backs up towards the kidneys
- Renal dysplasia - one or both kidneys do not form properly
- Renal hypoplasia - one or both kidneys are smaller than normal.
Infection in the kidney
A urinary tract infection (often called a UTI) happens when germs (usually bacteria) get into the urine and travel into the urinary system. In serious cases, this infection can travel into the kidney - this is called pyelonephritis.
Glomerulonephritis
Glomerulonephritis is a group of diseases in which the kidney filters, glomeruli, are damaged or inflamed (swollen). Children with this condition have blood and protein in their urine, as well as swelling of the body, especially around their face and legs.
Other problems
Rarely, acute hypertension is caused by other problems:
- a side-effect of some medicines – for example, a high dose (amount) of steroids, which may be given in hospital
- a problem with the endocrine system, which is the system of glands that controls many of the body’s functions – for example, a tumour in the adrenal gland, which is the gland that sits on top of the kidney
- a problem with the heart or the brain.
Long-term hypertension
- scars in the kidneys – these may also cause chronic urinary tract infections
- cystic kidneys – where the kidneys have cysts, round swellings that may be filled with a watery liquid
- renovascular disease – which affects the blood vessels in the kidneys.
Scars in the Kidneys
Some children have scars in the kidney – this is called renal scarring. Some children are born with these scars and do not have any other symptoms. Other children have urinary tract infections, which are caused by germs in the urine, because of the scars.
Cystic kidneys
Cystic kidneys are kidneys that have cysts on them. Cysts are round swellings that may be filled with a watery liquid. There are different types of diseases that cause cystic kidneys. Diseases that cause cystic kidneys include:
- autosomal recessive polycystic kidney disease
- autosomal dominant polycystic kidney disease
- multicystic dysplastic kidney.
Renovascular disease
In renovascular disease (or renal vascular disease), there is a problem with the blood vessels that carry blood to the kidney. Types of renal vascular disease include mid-aortic syndrome and renal artery stenosis.
Hypertension with chronic kidney disease
Malignant hypertension
Malignant hypertension is very high blood pressure.
Children with malignant hypertension usually have most of the symptoms described in the Symptoms section.
These children need quick and intensive treatment to control their blood pressure. They will need to be admitted to a specialist unit in the hospital that treats malignant hypertension.
Tests and diagnosis
Diagnosing hypertension
Measuring blood pressure
At hospital or GP clinic
Your child’s doctor or nurse measures your child’s blood pressure. An electronic or manual (worked by hand) instrument, which is the best type and size for your child, is used.
Measuring blood pressure in young children can be challenging especially if they are anxious or frightened. Your child’s doctor or nurse will take a few measurements when your child is relaxed. Your child may need to go back on three separate occasions for more measurements.
At home
Ambulatory blood pressure monitoring
One of the best ways to assess a child suspected of hypertension is to use ambulatory blood pressure monitoring (ABPM). Your child may be fitted with a special electronic monitor that automatically measures blood pressure over a period of time, usually 24 hours.
Examination
Your doctor will talk to you or your child about his or her symptoms and any medicines that he or she takes, and do an examination of your child.
Urine tests
Blood tests
Blood tests may be taken to check kidney and thyroid hormone levels in your child’s blood. A small amount of blood will be taken from a vein with a needle and syringe.
Other tests
If your child is diagnosed with hypertension, your doctor may arrange other tests.
Imaging test
- Ultrasound scan - looks at look at the shape and size of the kidneys and other parts of the urinary system. A small handheld device is moved around your child’s skin and uses sound waves to create an image on a screen.
- Electrocardiogram (ECHO) - checks the blood flow through the heart and how hard the heart has been working. Like an ultrasound scan, it uses sound waves to take images of your child’s heart.
- DMSA – shows whether there is any damage in the kidneys or other parts of the urinary system. A chemical that gives out a small amount of radiation is injected into one of your child’s blood vessels, and a special camera takes pictures.
Electrocardiogram (ECG)
An electrocardiogram (ECG) checks whether the heart is working too hard, or if there any problems with the heartbeat. Small sticky patches are put on your child’s arms, legs and chest, and connected to a machine.
Angiogram and angioplasty
If the arteries (blood vessels) that lead to the kidneys are too narrow, this means there is less blood flowing to the kidneys, which can lead to hypertension.
- An angiogram is a type of imaging test that looks at these arteries in detail. A general anaesthetic (GA) is used to make your child go to sleep so he or she does not feel pain anywhere in his body. The doctor makes a very small cut in the skin. He or she uses an ultrasound scanner as a guide, and inserts a needle through the cut into one of the large arteries in the body – usually one in the groin. A long thin tube called a catheter is passed through this artery until it reaches the artery leading to the kidney, and a special dye is placed through the catheter to flow to the kidney. X-ray images are taken.
- An angioplasty is a treatment that stretches the artery. This lets blood flow more easily to the kidney, and so helps reduce blood pressure. A small balloon is placed through the catheter and when it gets to the narrowed section, it inflates. After the procedure, the catheter is drawn back and removed, and the opening in the skin heals in a few days.
Referral
Depending on the results of these tests, your doctor may refer your child to:
- a paediatrician, a doctor who treats babies, children and young people, and may be in a hospital or a clinic
- a paediatric nephrologist, a doctor in a paediatric renal unit (a specialised unit that treats babies, children and young people with kidney conditions) who specialises in treating babies, children and young people with kidney problems, and may need to confirm the diagnosis and advise on treatment.
Questions to ask the doctor or nurse
- What other tests will my child need?
- How do I help prepare my child for the tests?
- Why does my child have hypertension?
- How will you know if my child has an underlying condition? How can I get more information about that condition?
Treatment
Does my child need treatment?
If your child has hypertension, they will need to reduce and/or control their blood pressure. There are different ways to do this.
- For some children, hypertension can be controlled with a healthy diet and lifestyle, as well as medicines, over a period of time.
- For other children, hypertension is caused by an underlying condition that needs to be treated.
Your child’s doctor will recommend the treatments that are right for your child. This may include prescribing one or more medicines. If you have any questions or concerns, speak with your child’s doctor or nurse. Your views about treatment will be considered.
It is important that your child follows the treatment plan agreed with your doctor. If their blood pressure is not controlled, they are at higher risk of stroke, heart attack and heart failure. They are also at higher risk of damaging their kidneys.
Eating and drinking
Your child may need to change what they eat and drink. Speak to the doctor or nurse for more information. Below are some tips you can follow as a family to keep your child’s blood pressure healthy.
Eat less salt
Reducing the amount of salt you eat can help to control blood pressure. Avoid eating or drinking lots of salted nuts, crisps, crackers, soft drinks, fast food meals, takeaways and processed foods (meals that are pre-prepared, including soups) – these often have more salt than we think. Do not add extra salt to meals that you cook or at the dining table.
Eat a healthy diet
Eat lots of fresh fruits and vegetables. Swap white bread, rice and pasta for whole-wheat varieties. Avoid food and drinks with lots of added sugar (including sweets, sugary cereals, high-sugar squash and fizzy drinks or sodas). Limit caffeine (which is found in coke drinks, tea and coffee).
Drinks
Your doctor will advise you on how much fluid (such as water) your child should drink.
If your child has a kidney condition
Sports and activities
Medicines
Your child’s doctor may prescribe medicine to control or reduce their blood pressure, in order to treat hypertension. A few children with hypertension need to take medicine to control blood pressure for the rest of their life.
Never stop the medicine without telling your doctor or nurse.
Medicines for Children – information about giving medicines to children
Which medicines are used
There are many medicines used to treat hypertension in children. Your doctor will prescribe the medicine that they think is best for your child.
- angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) – common medicines include captopril, enalapril, lisinopril, losartan, valsartan
- calcium-channel blockers – including amlodipine, nicardipine, nifedipine, nimodipine
- Beta-blockers – including atenolol, carvedilol, esmolol, labetalol, metoprolol, propranolol, sotalol
- alpha-blockers - including doxazosin, phenoxybenzamine, prazosin
- vasodilators – including hydralazine, methyldopa, minoxidil
- diuretics - including amiloride, bendroflumethiazide, bumetanide, chlorothiazide, chlortalidone, furosemide, metolazone, spironolactone
Angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) relax blood vessels. ARBs may also be called angiotensin II receptor antagonists.Common medicines: captopril, enalapril, lisinopril, losartan, valsartan
Calcium-channel blockers widen blood vessels so the blood flows more easily. Common medicines: amlodipine, nicardipine, nifedipine, nimodipine
Beta-blockers make the heart beat more slowly and with less force. They may also be called beta-adrenoceptor-blocking medicines. Common medicines: atenolol, carvedilol, esmolol, labetalol, metoprolol, propranolol, sotalol
Alpha-blockers relax the blood vessels, making it easier for blood to flow through them. They are also called alpha-adrenoceptor-blocking medicines. Common medicines: doxazosin, phenoxybenzamine, prazosin
Vasodilators widen blood vessels so the blood flows more easily. Common medicines: hydralazine, methyldopa, minoxidil
Diuretics get rid of extra water and salt into urine, which affects the blood pressure. Common medicines: amiloride, bendroflumethiazide, bumetanide, chlorothiazide, chlortalidone, furosemide, metolazone, spironolactone
General information about medicines for hypertension
- It is important that your child continues taking the prescribed medicine. If you are not sure a medicine is working or think it is no longer needed, contact your doctor but continue to give the medicine as usual in the meantime. Do not give extra doses as you may do harm.
- Contact your doctor straight away if your child is vomiting (being sick) and cannot take their medicine for more than 24 hours.
- Check with your doctor or pharmacist before giving any other medicines to your child. This includes paracetamol, ibuprofen, herbal or complementary medicines.
- Only give the medicine to your child. Never give it to anyone else, even if they have high blood pressure, as this could do harm.
- If you think someone else may have taken the medicine by accident, contact your doctor straight away.
Side-effects
Sometimes medicines have other effects that we don’t want - side-effects. Your child’s doctors will check the side-effects and if the medicine is working. They may need to change the medicine so that it is right for your child.
Let your doctor know if your child has any of the following side-effects:
- feeling tired or drowsy
- a dry cough
- dizziness, faintness or light-headedness
- a skin rash
- headaches
- poor sleeping.
Other side-effects to watch out for
- With some medicines, your child may grow more hair around their body. If you are concerned, speak to your doctor about it at your next visit.
- If your child takes some blood pressure medicines for a long time (several months), their gums may become tender or swollen, and may bleed when they brush their teeth. They will return to normal when the treatment is stopped. Brushing their teeth with a soft toothbrush and regular flossing will help. If you are concerned, contact your doctor or dentist.
- Your child’s ankles may swell (get bigger).
Questions to ask the doctor or nurse
- Do I need to make any changes to what my child eats and drinks? How can I get more information and support about this? How can I get more information and support about this?
- Can my child take part in all types of sports and activities?
- How often do I need to measure my child’s blood pressure at home?
- What is the acceptable range for my child’s blood pressure?
- What do I do if the blood pressure readings are too high?
-
When do I need to call or come back to my child’s doctor or the hospital?
About the future
Long-term effects
Hypertension can be a serious condition if it is not well controlled. Hypertension increases the risk of other diseases, especially if it continues into adulthood. These include stroke, heart attack, heart failure and kidney disease.
Your child’s blood pressure will need to be carefully controlled to reduce the risk of other diseases. If your child has an underlying condition, they will also need treatment for that.
School and play
Children with hypertension can generally do all of the things that other children their age do, as long as their blood pressure is well controlled.
Follow up appointments
Your child may need to go back to your doctor or to the hospital to have their blood pressure checked, or for further tests or treatment.
Your child may need to see a paediatrician (children’s doctor) in your local hospital, or to see a specialist paediatrician. Your doctor will let you know what to expect.
Contact your doctor straight away if your child is vomiting (being sick) and cannot take his or her medicine for more than 24 hours (1 day).
Monitoring blood pressure
- 4 years old: 95 mmHG
- 8 years old: 100 mmHG
- 12 years old: 110 mmHG
- 16 years old: 115 mmG
Your doctor or nurse may ask you to check your child’s blood pressure at home or over 24 hours.
Other procedures
If your child is having another procedure at hospital, tell the doctor there that they have hypertension, and give a list of the medicines they are taking. They may need to stop one or more medicines.
Impact on your child
Children with hypertension can generally do all of the things that other children their age do, as long as their blood pressure is well controlled.
Getting support
This can be a difficult and stressful experience for your child and the whole family, including other children.
If you have any concerns or need additional support, speak with your doctor or nurse.
Further information
This is the end of the information on hypertension. If you would like to read more about other conditions affecting the kidneys, tests and diagnosis, treatment or supporting information, you can find a list of topics covered on the infoKID website at www.infoKID.org.uk.