Intermittent claudication


Intermittent claudication

Symptoms of peripheral arterial disease

Many people with peripheral arterial disease (PAD) don't have any symptoms. However, you may feel painful aching in your leg muscles that is triggered by physical activity, such as walking or climbing stairs.

The pain, known as intermittent claudication, usually develops in your calves, but your hip, buttock or thigh muscles can be affected.

The pain can range from mild to severe, and will usually go away after a few minutes when you rest your legs.

Both legs are often affected at the same time, although the pain may be worse in one leg.

Other symptoms of PAD can include:

hair loss on your legs and feet

numbness or weakness in the legs

brittle, slow-growing toenails 

ulcers (open sores) on your feet and legs, which don't heal

changing skin colour on your legs, such as turning pale or blue

shiny skin 

in men, erectile dysfunction

the muscles in your legs shrinking (wasting)

The symptoms of PAD often develop slowly, over time. If your symptoms develop quickly, or get suddenly worse, it could be a sign of a serious problem requiring immediate treatment (see below).

When to seek medical advice

See your GP if you experience recurring episodes of leg pain after physical activity, especially if you smoke, or have a confirmed diagnosis of diabetes, high blood pressure and/or high cholesterol.

Many people mistakenly think recurring episodes of leg pain are part of growing older. This is not the case – there is no reason why an otherwise healthy person should experience leg pain.

When to seek urgent medical advice

Some symptoms may suggest that the supply of blood to your legs has become severely restricted, and you may need to see a doctor urgently. These include:

your symptoms getting suddenly worse

constant leg pain, even when resting

being unable to move the affected leg

a sudden loss of normal sensation in the affected leg, or a burning or prickling sensation

a difference in the colour and temperature of your legs

persistent ulcers on one or both legs

the muscles in your legs beginning to waste away

the skin on your toes or lower limbs turning red and then black and/or beginning to swell and produce foul-smelling pus, causing severe pain (gangrene)

If you experience any of the problems listed above, contact your GP as soon as possible. If this is not possible,  your localout-of-hours service. 

These symptoms could be a sign of a complication of PAD called critical limb ischemia (CLI), which requires urgent treatment. 

Causes of peripheral arterial disease

Peripheral arterial disease (PAD) is usually caused by a build-up of fatty deposits on the walls of the arteries inside the legs. The fatty deposits, called atheroma, are made up of cholesterol and other waste substances.

The build-up of atheroma on the walls of the arteries makes the arteries narrower and restricts the flow of blood to the legs. This process is called atherosclerosis.

People with PAD can experience painful aching in their leg muscles during physical activity, because the muscles are not receiving the blood supply they need.

Like all tissue in your body, muscles in your legs need a constant supply of blood to function properly. When you are using your leg muscles, the demand for blood increases significantly. But if the arteries in your legs are blocked, the supply of available blood cannot meet the demand.

This shortfall between supply and demand causes your muscles to experience painful aches, which usually get better when you rest your legs.

Increased risk

There are some risk factors for PAD that cannot be changed, such as a family history of heart disease and atherosclerosis, or your age.

As you get older, your arteries naturally begin to harden and get narrower, which can lead to atherosclerosis and then PAD.

However, there are many things that can dangerously speed up this process, which are described below.


Smoking is the single most important factor that increases your risk of PAD. Smoking can damage the walls of your arteries. Tiny blood cells, known as platelets, will then form at the site of the damage to try to repair it, which can cause your arteries to narrow.

It is estimated that more than 9 out of every 10 people who develop PAD smoke or have done so in the past.


If you have poorly controlled type 1 diabetes or type 2 diabetes, the excess glucose in your blood can damage your arteries and increase your risk of developing PAD. Around 2 out of every 10 people with PAD has diabetes.

People who have poorly controlled diabetes and PAD are also more likely to eventually need an amputation as a result of severely restricted blood flow to the legs.

High cholesterol

Cholesterol is a type of fat that is essential for the body to function.

There are two main types of cholesterol:

Low-density lipoprotein (LDL) is the main cholesterol transporter, and carries cholesterol from your liver to cells that need it. If there is too much cholesterol for the cells to use, this can cause a harmful build-up in your blood and lead to atherosclerosis. For this reason, LDL cholesterol is sometimes called "bad cholesterol".

High-density lipoprotein (HDL) carries cholesterol away from the cells and back to the liver, where it is either broken down or passed from the body as a waste product. For this reason, it's sometimes called "good cholesterol".

Most of the cholesterol your body needs is made by your liver. However, if you eat foods high in saturated fat, the fat is broken down into LDL, which is then passed into your blood vessels.

High blood pressure

Your arteries are designed to pump blood at a certain pressure, and if blood pressure is too high (known as hypertension), the walls of the arteries can become damaged.

High blood pressure can be caused by:

being overweight

drinking excessive amounts of alcohol



a lack of exercise

Diagnosing peripheral arterial disease

If your GP suspects peripheral arterial disease (PAD), they will carry out a physical examination of your legs.

PAD can cause various symptoms – some of which your GP will be able spot, but you may not – such as:

shiny skin

brittle toenails

hair loss on your legs and feet

the pulse in your leg being very weak or undetectable

leg ulcers

Your GP may also ask about your symptoms and your personal and family medical histories.

The ankle brachial pressure index

The ankle brachial pressure index (ABPI) test is widely used to diagnose PAD, as well as assessing how well you are responding to treatment.

While you rest on your back, your GP or practice nurse will measure the blood pressure in your upper arms and your ankles. These measurements are taken with a Doppler probe, which uses sound waves to determine the blood flow in your arteries.

They then divide the second result (from your ankle) by the first result (from your arm).

If your circulation is healthy, the blood pressure in both parts of your body should be exactly or almost the same, and the result of your ABPI would be one.

However, if you have PAD, the blood pressure in your ankle will be lower due to a reduction in blood supply, so the results of the ABPI would be less than one.

In some cases, ABPI may be carried out after getting you to run on a treadmill or cycle on an exercise bike. This is a good way to see the effect of physical activity on your circulation, although it will usually need to be done in hospital, as most GP surgeries do not have the facilities to perform this test.

Further testing

In most cases, your GP will be able to confirm a diagnosis of PAD by doing a physical examination, asking about your symptoms and checking your ABPI score.

Further testing is usually only required if:

there is uncertainty about the diagnosis – for example, if you have leg pain but your ABPI score is normal

you do not fit the expected profile of somebody with PAD – for example, you are young and have never smoked

the restriction of blood supply in your leg is severe enough that treatment, such as surgery, may be required

Additional hospital-based tests that can be used include:

an ultrasound scan – where sound waves are used to build up a picture of arteries in your leg; this can identify exactly where in your arteries there are blockages or narrowed areas

an angiogram – wherea special liquid known as a contrast agent is injected into a vein in your arm; the agent shows up clearly on a computerised tomography (CT) scan or magnetic resonance imaging (MRI) scan and produces a detailed image of your arteries

In some cases, the contrast agent may be injected directly into the arteries of your leg, and X-rays may be used to produce the images.

Treating peripheral arterial disease 

There is no cure for peripheral arterial disease (PAD), but lifestyle changes and medication can help reduce the symptoms.

These treatments can also help reduce your risk of developing other types of cardiovascular disease (CVD), such as coronary heart disease, stroke and heart attack.

This is very important, because having PAD is a sign that your blood vessels are unhealthy, which can mean you are more likely to develop one of these potentially more serious problems.

Surgery may be used in severe cases or when initial treatment has not effectively reduced your symptoms.

Lifestyle changes

The two most important lifestyle changes that you can make if you are diagnosed with PAD are exercising more regularly and stopping smoking, if you smoke.


Evidence suggests that regular exercise helps to reduce the severity and frequency of PAD symptoms, while also reducing the risk of developing another CVD.

The National Institute for Health and Care Excellence (NICE)recommends supervised exercise as one of the first steps for managing PAD. This may involve group exercise sessions with other people with CVD, led by a trainer.

The exercise programme usually involves two hours of supervised exercise a week for three months. Ideally, over time, you should be aiming to exercise daily for the rest of your life, as the benefits of exercise are quickly lost if it is not frequent and regular. 

One of the best exercises you can do is walking. It is normally recommended that you walk as far and as long as you can before the symptoms of pain become intolerable. Once this happens, rest until the pain goes, and begin walking again until the pain returns.

Keep using this "stop-start" method until you have spent at least 30 minutes walking in total. This should ideally be repeated several times a week.

You will probably find the exercise course challenging, as the frequent episodes of pain can be upsetting and off-putting. However, if you persevere, you should gradually notice a marked improvement in your symptoms, and you will begin to go longer periods without experiencing pain.

Stop smoking

Stopping smoking will reduce your risk of PAD getting worse and another serious CVD developing.

Research has found that people who continue to smoke after receiving their diagnosis are much more likely to have a heart attack and die from a complication of heart disease than people who quit after receiving their diagnosis.

Other lifestyle changes

In addition to exercising and stopping smoking, there are a number of other lifestyle changes you can make to reduce your risk of developing other forms of CVD.

These include eating a healthy diet, maintaining a healthy weight and cutting down on alcohol.


Different medications can be used to treat the underlying causes of PAD, while also reducing your risk of developing another CVD.

Some people may only need to take one or two of the medications discussed below, while others may need all of them.


If blood tests show that your levels of LDL cholesterol ("bad cholesterol") are high, you will be prescribed a type of medication called a statin.

Statins work by helping to reduce the production of LDL cholesterol by your liver.

Many people who take statins experience no or very few side effects, although others experience some troublesome – but usually minor – side effects, such as indigestion, headaches or feeling sick (nausea).


Antihypertensives are a group of medications used to treat high blood pressure (hypertension).

It's likely that you will be prescribed an antihypertensive drug if your blood pressure is higher than 140/90mmHg if you do not have diabetes, or 130/80mmHg if you do have diabetes. Read our page on diagnosing high blood pressure for more information about how blood pressure is measured.

A widely used type of antihypertensive is an angiotensin-converting enzyme (ACE) inhibitor, which block the actions of some hormones that help regulate blood pressure. They help to reduce the amount of water in your blood and widen your arteries, both of which will decrease your blood pressure.

Side effects of ACE inhibitors include:


tiredness or weakness


a persistent dry cough

Most of these side effects pass in a few days, although some people find they have a dry cough a bit longer.

If your side effects become particularly troublesome, a medication that works in a similar way to ACE inhibitors, known as an angiotensin-2 receptor antagonist, may be recommended.


One of the biggest potential dangers if you have atherosclerosis is a piece of fatty deposit (plaque) breaking off from your artery wall. This can cause a blood clot to develop at the site of the broken plaque.

If a blood clot develops inside an artery that supplies the heart with blood (a coronary artery), it can trigger a heart attack. Similarly, if a blood clot develops inside any of the blood vessels going to the brain, it can trigger a stroke.   

If you have PAD, you will probably be prescribed an antiplatelet medication to reduce your risk of blood clots. This medication reduces the ability of platelets (tiny blood cells) to stick together, so if a plaque does break apart, you have a lower chance of a blood clot developing.

Low-dose aspirin and clopidogrel are two antiplatelet medications often prescribed for people with PAD.

Common side effects of low-dose aspirin include indigestion and an increased risk of bleeding.

Common side effects of clopidogrel can include:

headaches or dizziness

feeling sick

diarrhoea or constipation


stomach (abdominal) pain

an increased risk of bleeding


Naftidrofuryl oxalate

NICE recommends naftidrofuryl oxalate for the treatment of leg pain triggered by exercise (intermittent claudication) in people with PAD.

This medication may improve blood flow in the body, and is very occasionally used if you prefer not to have surgery or your supervised exercise programme has not led to a satisfactory improvement in your condition.

Side effects of naftidrofuryl oxalate can include:

feeling sick

abdominal pain



You will normally be advised to take naftidrofuryl oxalate for around three to six months, to see if it improves your symptoms. If the treatment is not effective after this time, it will be stopped.

Surgery and procedures

In a few cases, a procedure to restore the flow of blood through the arteries in your legs may be recommended. This is known as revascularisation.

Revascularisation may be recommended if your leg pain is so severe that it prevents you from carrying out everyday activities, or if your symptoms have failed to respond to the treatments mentioned above.

There are two main types of revascularisation treatment for PAD – angioplasty and a bypass graft. Both techniques are outlined below.


Angioplasty is where a blocked or narrowed section of artery is widened by inflating a tiny balloon inside the vessel. 

A tiny hollow tube known as a catheter is inserted into one of the arteries in your groin. The catheter is then guided to the site of the blockage.

On the tip of the catheter is a balloon, which is inflated when the catheter is in place. This helps widen the blood vessel. Sometimes a metal mesh "tube" known as a stent may be left in place permanently to help keep the artery open.

Bypass graft

A bypass graft is where blood vessels are taken from another part of your body and used to bypass the blockage in an artery.

During the operation, a length of healthy vein in your leg is removed. The vein is then joined (grafted) above and below the blocked vein so the blood supply can be rerouted, or bypassed, through the healthy vein. Sometimes a section of artificial tubing can be used as an alternative to a grafted vein.


Which procedure is best?

You may not always be able to choose between having an angioplasty or a bypass graft, but if you are, it's important to be aware of the advantages and disadvantages of each technique.

An angioplasty is less invasive than a bypass (it doesn't involve making major incisions in your body) and is usually performed under a local anaesthetic as a day procedure. This means you will be able to go home the same day you have the operation, and you may recover more quickly.

For this reason, angioplasty is generally preferred to bypass surgery, unless angioplasty is not suitable or has failed previously.

However, the results of a bypass are generally considered to be longer-lasting than those of an angioplasty, and the procedure may therefore need to be repeated less often than an angioplasty may need to be.

Both angioplasty and bypass surgery carry a small risk of serious complications, such as a heart attack, stroke and even death. While there are few studies comparing the two techniques for PAD, there is some evidence to suggest that the risk of serious complications is similar in both bypass surgery and angioplasty.

Before recommending treatment, a team of specialist surgeons, doctors and nurses will discuss options with you – including the potential risks and benefits.

Complications of peripheral arterial disease 

The blockages in the arteries that cause peripheral arterial disease (PAD) can also lead to other serious problems, such as critical limb ischaemia (CLI).

Critical limb ischaemia

CLI occurs in cases of PAD where the blood flow to the legs becomes severely restricted. It's estimated that around one in every five people with symptoms of PAD will develop CLI at some point.

Symptoms of CLI include:

a severe burning pain in your legs and feet that continues even when you are resting

your skin turning pale, shiny, smooth and dry

wounds and ulcers (open sores) on your feet and legs that don't heal

loss of muscle mass in your legs

the skin on your toes or lower limbs becoming cold and numb, turning red and then black, and/or beginning to swell and produce foul-smelling pus, causing severe pain (gangrene) 

If you think you are developing symptoms of CLI, contact your GP immediately. If this is not possible, telephone your local out-of-hours service. 

CLI is an extremely serious complication that can be challenging to treat.

An angioplasty or bypass graft (read about treating PAD for more information on these operations) will usually be recommended if you have CLI, although these may not always be successful or possible. In a few cases, an amputation below the knee may be required.

Increased risk of cardiovascular disease

Cardiovascular disease (CVD) is a general term that describes a condition affecting the heart or blood vessels. Along with PAD, there are a number of different forms of CVD – including coronary heart disease, stroke, heart attack and angina.

While PAD itself does not directly cause other forms of CVD, the condition is a sign that the blood vessels in your legs are in bad health.

The blockages in the arteries in the legs that cause PAD can also affect other areas of your body, such as the arteries supplying the heart and brain, which means that having the condition makes you more likely to develop another form of CVD.

Preventing peripheral arterial disease

The most effective way to prevent peripheral arterial disease (PAD) or stop the condition getting worse is to tackle the build-up of fatty substances in your arteries (atherosclerosis).

There are five main ways you can achieve this:

eat a healthy diet

stop smoking, if you smoke

exercise regularly

lose weight, if you are overweight or obese

moderate your consumption of alcohol

These lifestyle changes are discussed in more detail below.

Healthy diet

Eating an unhealthy diet that is high in fat can cause fatty plaques to build up in your arteries. This is because fatty foods contain cholesterol.

There are also two types of fat – saturated and unsaturated. Avoid foods containing saturated fats, because they will increase the levels of "bad cholesterol" in your blood.

Foods high in saturated fat include:

meat pies

sausages and fatty cuts of meat


ghee (a type of butter often used in Indian cooking)



hard cheese

cakes and biscuits

food that contains coconut or palm oil

However, it is not healthy to completely cut out all types of fat from your diet. It is important to replace saturated fats with unsaturated fats, as they can help increase levels of "good cholesterol" and reduce blockage in your arteries.

Foods that are high in unsaturated fat include:

oily fish (mackerel, salmon, tuna)


nuts and seeds

sunflower, rapeseed and olive oil

Eating a low-fat diet including lots of fibre, such as wholegrain rice, bread and pasta, and plenty of fruit and vegetables, may also help to lower cholesterol. Fruit and vegetables are full of vitamins, minerals and fibre, and help keep your body in good condition. Aim to eat five 80g portions of fruit and vegetables every day.

Stop smoking

If you smoke, it is strongly recommended that you quit as soon as possible.

If you decide to stop smoking, your GP can refer you to an  service, which will offer dedicated help and advice about the best ways to quit.

You can also call the Smokefree helpline on 0300 123 1044 (7am to 11pm). The specially trained helpline staff offer free expert advice and encouragement.

If you are committed to giving up smoking but do not want to be referred to a stop smoking service, your GP should be able to prescribe treatment to ease your withdrawal symptoms.

Exercise regularly

If you do not have PAD, a minimum of 150 minutes of vigorous exercise a week is recommended. The exercise should be strenuous enough to leave your heart beating faster, and you should feel slightly out of breath afterwards.

Activities you could incorporate into your exercise programme include:

brisk walking

hill climbing




If you find it difficult to achieve 150 minutes of exercise a week, start at a level you feel comfortable with. For example, you could do 5 to 10 minutes of light exercise a day and then gradually increase the duration and intensity of your activity as your fitness begins to improve.

Maintain a healthy weight

If you are overweight or obese, aim to lose weight and maintain a healthy weight by using a combination of regular exercise and a calorie-controlled diet.

Cut down on alcohol

If you drink alcohol, do not exceed recommended daily limits (three to four units a day for men and two to three units a day for women).

A unit of alcohol is roughly half a pint of normal-strength lager or a single measure (25ml) of spirits.

Regularly exceeding recommended alcohol limits can raise your blood pressure and cholesterol level, which can cause your blood vessels to become damaged or narrowed.

Contact your GP if you find it difficult to moderate your drinking. Counselling services and medication can help you reduce your alcohol intake.