Amlodipine

What is amlodipine?

Amlodipine, also sold as the brand name Istin, is a medication used to treat high blood pressure (hypertension). Amlodipine is a type of calcium channel blocker. This means it blocks the calcium channels in your body, which helps to relax and widen the blood vessels. This widening of the blood vessels means that blood can flow through them more easily, reducing your blood pressure.

How does amlodipine work?

Amlodipine treats high blood pressure and prevents heart attacks, heart disease and strokes from occurring in the future. As a calcium channel blocker, amlodipine interferes with the action of calcium, which usually causes narrowing of your blood vessels. By blocking the action of calcium, the blood vessels relax, and blood flows more freely around the body. Amlodipine is also used to treat angina (chest pain), helping blood reach the heart more efficiently.

How quickly does amlodipine work?

Amlodipine will start to work from day one, although it may take a few weeks before making a real difference. High blood pressure often won’t cause symptoms, so you may not feel any different. This doesn’t mean that you should stop taking your medicine. If you are taking it to treat angina, you will usually notice an improvement in your symptoms after a number of weeks.

How can I tell if amlodipine is working?

Having regular checkups with your doctor where your blood pressure is measured is the best way to check how well the amlodipine is working. You may also be able to use a home blood pressure monitor, to keep an eye on your own blood pressure between appointments. 

Active ingredients

The active ingredient is amlodipine mesilate monohydrate. Each tablet contains either 5 or 10mg, depending on the dose of the tablet.

Inactive ingredients

The other ingredients in amlodipine tablets are microcrystalline cellulose, calcium hydrogen phosphate, sodium starch glycollate type A and magnesium stearate. 

Please note: inactive ingredients may vary between different brands of generic amlodipine.

How to take amlodipine?

Amlodipine is usually taken once a day, and you should always follow the instructions given by your doctor. You should take it at the same time each day, and it doesn’t have to be taken with food. You should avoid consuming grapefruit or grapefruit juice while you are taking amlodipine as the fruit can increase the level of amlodipine in the body, making you more likely to suffer from side effects.

Can amlodipine tablets be crushed or split?

You can dissolve the tablets in a glass of water if you find that easier, provided you drink it immediately. Always take the prescribed dose, either as a full tablet or by measuring it out if the amlodipine is in liquid form.

Amlodipine side effects

Not everyone will experience the side effects listed, and some are more common than others. 

Common or very common side effects include:

• Dizziness
• Flushing
• Headaches
• Abdominal pain
• Drowsiness
• Nausea or vomiting
• Swollen ankles
• Skin reactions
• Tachycardia (a faster-than-normal heartbeat)
• Palpitations (the sensation of a pounding heartbeat)
• Constipation or diarrhoea
• Indigestion
• Breathlessness
• Muscle cramps
• Disorders of vision

More than 1 in 100 people will experience these side effects, which usually subside after the first few weeks. 

Uncommon side effects (occur in less than 1 in 100 people) include:

• Angioedema (a rapid onset swelling of the skin)
• Erectile dysfunction
• Gum swelling
• Numbness
• Fainting
• Hair loss
• Anxiety
• Arrhythmia (unusual heart rhythm)
• Chest pain
• Cough
• Dry mouth
• Gynaecomastia (breast enlargement)
• Increased sweating
• Low blood pressure
• Difficulty sleeping
• Tiredness
• Changes in mood, including depression
• Runny nose
• Changes in taste
• Tinnitus (a ringing in the ears)
• Tremor
• Urinary disorders
• Weight change

Rare or very rare side effects include:

• Confusion
• Liver dysfunction
• High blood sugar
• Hypersensitivity
• Changes to blood counts
• Heart attack
• Pancreatitis
• Sensitivity to sunlight
• Stevens-Johnson syndrome (a skin disorder characterised by a blotchy rash)
• Vasculitis (inflammation of the vessels, causing a rash)

Serious side effects, which would necessitate medical attention include: 

• Severe stomach pain, bloody diarrhoea, feeling sick, and vomiting are signs of pancreatitis.
• Jaundiced skin (yellowing of the skin or eyes) 
• Chest pain
• Allergic reaction - which may involve a severe or itchy rash, wheezing or trouble breathing, tightness in the throat or chest, and swelling of the face

Contraindications

Amlodipine is not suitable for the following groups of people:

• Those who are allergic to amlodipine or any of the excipients
• Children younger than six
• Pregnant women or women who are breastfeeding
• Those with significantly low blood pressure (hypotension)
• Those with unstable heart failure following a heart attack
• Those with certain heart valve problems (e.g. aortic stenosis)
• People with liver or kidney disease or if you have suffered from a heart attack recently or have heart failure.

You should tell your doctor if any of the following apply:

• You have liver problems
• You have kidney problems
• You have suffered from a heart attack recently
• You have any heart conditions such as valvular heart disease or heart failure
• You have had a reaction to other medicines in the past
• You are over the age of 65
• You have peripheral vascular disease
• You are diabetic
• You have high cholesterol
• You are on a low-salt diet
• You are dehydrated or prone to dehydration for any reason
• You have primary aldosteronism

Drug interactions

You should inform your doctor of any other medications you are taking, in particular: 

• Other medications designed to lower your blood pressure
• Antibiotics such as erythromycin, clarithromycin and rifampicin
• Antifungals such as Itraconazole or ketoconazole
• Medications used to treat HIV or hepatitis C
• Medicines to treat epilepsy 
• Immune suppressors such as tacrolimus or ciclosporin
• Simvastatin to lower the cholesterol
• St John’s Wort (a herbal remedy)

Amlodipine and alcohol

You can drink alcohol while taking amlodipine, but it can enhance the effect on your blood pressure, leaving you feeling sleepy, dizzy or causing headaches. If you get these side effects, you may want to consider cutting out alcohol for the duration of your treatment.

Amlodipine and pregnancy

Amlodipine is not safe to take during pregnancy as it can be harmful to a developing baby. Alert your doctor right away if you fall pregnant while you are taking this medicine. There are safer alternatives they can recommend. 

Can amlodipine affect my contraception?

While amlodipine won’t affect your contraception, the combined oral contraceptive pill can reduce the effectiveness of amlodipine as it can cause high blood pressure itself. If you have high blood pressure, it’s unlikely that you’ll be suitable for the combined oral contraceptive pill, so you should speak to your doctor or pharmacist about an appropriate alternative. 

Can you take amlodipine with paracetamol?

It’s fine to take paracetamol with amlodipine, but you should always inform your doctor of any additional medicines you are taking, including over the counter or herbal remedies, in case they cause interference.

Can amlodipine be used for Raynaud's syndrome?

Raynaud’s syndrome, where the circulation is reduced to the fingers and toes when you get too cold, can be treated with amlodipine. It helps to get your blood flowing more freely, which can reduce discomfort and boost your circulation. Only ever take medication for the purpose for which it was prescribed.

Could amlodipine affect my fertility?

There is no evidence to suggest that amlodipine will affect female fertility. But, it may be possible that amlodipine reduces sperm count in men; however, there is limited evidence. However, untreated high blood pressure is also associated with reduced sperm quality.

Will amlodipine affect my sex life?

While some types of medications for high blood pressure can cause erectile dysfunction, it’s rare for amlodipine to have this effect. There are no known effects on female sexual function.

How to cope with amlodipine side effects?

If you experience headaches, these shouldn’t last longer than a week. Drinking plenty of fluids, resting and taking painkillers can help to manage this. If you get dizzy after taking amlodipine, either sit or lie down until the dizziness passes. Cutting down on alcohol, coffee and tea will help to ease facial flushing and raising your legs at a 90-degree angle can ease swollen ankles.

Can I make lifestyle changes instead of taking amlodipine?

Making healthy changes to your lifestyle will improve the health of your heart and have a positive effect on your blood pressure. Some things you can do include: 

• Staying active – you should aim for a minimum of 30 minutes of exercise per day
• Reduce your salt intake – adults should be consuming a maximum of 6g of salt a day
• Reduce your intake of saturated fats
• Lose weight – if you are overweight, this puts strain on your heart
• Eat plenty of fruit and vegetables

Always consult your doctor first. You may still need to take amlodipine to manage your blood pressure.

Amlodipine vs other calcium channel blockers

The different variety of calcium channel blockers available work in different ways. Which medicine is best for you will depend on what condition you are being treated for, the severity of your symptoms and other factors such as age. Other calcium channel blockers include nifedipine, felodipine, lercanidipine, diltiazem and verapamil. Some of these are used to treat other conditions aside from hypertension.

Is amlodipine a statin?

Amlodipine belongs to a group of medicines called calcium-channel blockers used to reduce blood pressure, whereas a statin is used to reduce cholesterol.

What happens if I stop taking amlodipine?

If you stop taking amlodipine, your blood pressure is likely to rise again. You should continue to take it as prescribed even if your blood pressure has improved.

Can I drive when taking amlodipine?

If amlodipine makes you dizzy, then you shouldn’t drive until the dizziness wears off. This can be dangerous both for you and others on the road.

Is amlodipine a cure?

Amlodipine is a long term treatment that, combined with a healthy lifestyle, manages your condition by keeping your blood pressure at the optimum level, reducing your risk of having heart problems as a result.

How can you make amlodipine work faster?

Making positive lifestyle changes may help amlodipine to work faster. Exercising, eating a healthy diet and watching your salt intake are important factors in maintaining a healthy heart.

Will I need amlodipine for the rest of my life?

It’s likely that you will need amlodipine for the rest of your life as this is a long term treatment. However, by continuing to take your medication, you are protecting yourself from having a heart attack or stroke in the future or from developing heart disease.

Can I stop taking amlodipine if my blood pressure if lower?

You should continue to take amlodipine even if your blood pressure becomes lower, as this means the medication is working. If you stop taking it, then your blood pressure is likely to return to its previous level. So you need to keep taking amlodipine to maintain a healthy reading.

How to store amlodipine?

You should store amlodipine at room temperature away from damp. It is a good idea to avoid keeping it inside the bathroom and to keep it in the original packaging. Always keep medications out of reach of children and pets.

Is amlodipine related to cancer risk?

Some observational studies have found that calcium channel blockers may be associated with a small increased risk of developing cancer. However, a large observational study found there was no association between the use of calcium channel blockers and an increased incidence of cancer. More research is required to come to more robust conclusions.

Are there withdrawal symptoms associated with amlodipine?

You should consult your doctor before you stop taking amlodipine, as the dose is usually gradually decreased to avoid a dangerous spike in blood pressure.

Is amlodipine addictive?

Amlodipine is not an addictive substance. 

Can I take amlodipine for migraines?

Amlodipine can be used to treat migraines, although there’s not enough evidence to show that this treatment is effective. It’s likely to be prescribed if other migraine treatments have been ineffective or aren’t suitable for any reason. Don’t try to self-medicate with amlodipine, only take it as prescribed.

Can I take amlodipine for anxiety?

While anxiety could cause a spike in your blood pressure, amlodipine is not designed to treat anxiety. The medicine relaxes your blood vessels but does not treat your mental health. If you are experiencing issues with anxiety, then seek help from your doctor.