Amlodipine and felodipine are common drugs used in the treatment of high blood pressure. Amlodipine is the most common medication prescribed in England for blood pressure, with felodipine somewhere in the middle of the most common high blood pressure medicines. This post reviews different aspects of amlodipine vs felodipine, with a focus on the most important information from the patient’s point of view.
Table of Contents
What class of drug do amlodipine and felodipine belong to?
Amlodipine and felodipine belong to the same class of medicines called calcium channel blockers (CCB). Amlodipine, felodipine and other calcium channel blockers are further subcategorised as the dihydropyridine calcium-channel blockers which differ in their actions from verapamil hydrochloride and diltiazem hydrochloride (another type of CCB).
What are amlodipine and felodipine used for?
Amlodipine and felodipine are commonly used for the treatment of high blood pressure. Additionally, amlodipine and felodipine can be used for the prevention of angina (chest pains caused by the inadequate blood supply to the heart).
Amlodipine vs felodipine mechanism of action
Amlodipine and felodipine belong to the same type of calcium channel blockers. Calcium channel blockers, as the name suggests, ‘block’ entry of calcium into the cells located in the heart and blood vessels. Calcium is used by cells in the process of muscle contraction. Consequently, muscles relax, and this leads to a reduction in blood pressure. `
Amlodipine vs Felodipine side effects
Calcium channel blockers as a class of medicines can cause side effects. A common side effect which may be experienced by patients taking CCB may include (BNF, 2022):
- Dizziness/drowsiness
- Flushing
- Headache
- Flushing
- Oedema (swelling/fluid accumulation, for example, ankle swelling)
- Tachycardia (fast heartbeat)
- Nausea
- Vomiting
- Skin reactions
BNF does not list any additional side effects for each drug. The risk of side effects is therefore similar for both drugs.
Amlodipine vs felodipine: formulations
Amlodipine comes in the following forms and strengths:
- Amlodipine 2.5mg tablets
- Amlodipine 2.5mg tablets
- Amlodipine 10mg tablets
- Oral solution of various strengths
Amlodipine is most commonly prescribed as a generic brand (several generic manufacturers), but also as a branded medication called Istin tablets (Istin 5mg and Istin 10mg)..
Felodipine tablets come in modified release (prolonged-release or XL) form. Different brands of felodipine tablets are available in the market in a modified-release form in the following strengths:
- Felodipine 2.5 mg prolonged-release tablets
- Felodipine 5 mg prolonged-release tablets
- Felodipine 10 mg prolonged-release tablets
Some brands of felodipine modified-release tablets include Carioplen XL, Felotens XL, Neofel XL, Parmid XL, Pinefeld, Vascalpha).
How are amlodipine and felodipine taken?
Amlodipine and felodipine are usually taken once daily.
Which drug is more popular?
I recently reviewed the most common high blood pressure drugs prescribed in England. Amlodipine is the most popular high blood pressure medication with over 32.7 prescriptions issued in the last 12 months. Felodipine ranked 8th with 3.4 mln prescriptions issued in the same period. One reason for the extreme popularity of amlodipine over felodipine is the price difference between each drug. Looking at prescribing statistics for 12 months, the average cost of amlodipine per prescription issued is £1.18, whereas for felodipine is £5.94. Felodipine is more less 5x more expensive than amlodipine.
Recommendation on prefered prescribing of amlodipine comes from the NICE guide on hypertension, which recommended prescribing medicines which are taken once daily and by minimising the cost (NICE, 2022). The cost of the drug is therefore an important factor in prescribing. Other factors which are considered regarding whether to prescribe amlodipine or felodipine include tolerability to the drug and any potential interactions with drugs already taken by a patient.
An example of important interaction which may be considered is between amlodipine and simvastatin (a popular drug taken to reduce cholesterol). risk of myopathy (disease of the muscles) and rhabdomyolysis (breakdown of muscle into a bloodstream) is increased when amlodipine is taken with simvastatin. Amlodipine does not interact with other statins, for example, atorvastatin (UKMi, 2020).
Felodipine on the other hand does not interact with any statins (ibid).
Amlodipine vs felodipine: which drug is more effective?
In the UK most commonly prescribed calcium channel blockers are amlodipine and felodipine with amlodipine almost 10x more prescribed than amlodipine.
A limited number of studies compared the effectiveness of amlodipine vs felodipine in the treatment of high blood pressure. In one study (Ostergren et al., 1998), 260 patients were randomly given amlodipine or felodipine. After 4 weeks, more patients responded to the treatment with amlodipine than felodipine, especially when blood pressure was measured at night. After 8 weeks 82% of patients who took amlodipine and 69% who took felodipine achieved their target blood pressure.
The above study and other studies are small (number of patients enrolled on the study) and therefore overall data is of limited use.
FAQ
Can you take amlodipine and felodipine together?
Amlodipine and felodipine belong to the same class of drugs. It is unlikely that a doctor would prescribe amlodipine and felodipine together since both drugs have a similar mechanism of action and are licensed to treat the same conditions.
Why you should not take amlodipine?
Amlodipine is on of the most popular high blood pressure medicines. Although associated with some common side effects, amlodipine can effectively reduce high blood pressure. If untreated, high blood pressure may lead to long term complications and more serious disease. Very reary amlodipine is associated with serious side effects.
What is the first drug of choice for hypertension?
First drug choice for hypertension depends on the age, ethnicity and other concomitant conditions, especially diabetes. ACE Inhibitors (for example ramipril) or calcium Channel Blockers (for example amlodipine) are considered first-line choice for hypertension, depending on three above factors.
Is amlodipine a good blood pressure medicine?
Amlodipine is one of the most commonly prescribed medicines to treat high blood pressure. Amlodipine can affectively reduce blood pressure and is considered a first-line drug treatment for many patients, however, the choice of treatment depends on patient's age, ethnicity and presence of diabetes.
What is amlodipine 5 mg prescribed for?
In the UK amlodipine 5 mg is prescribed commonly for the treatment of high blood pressure. Amlodipine can also be use for the prevention of angina.
References:
BNF (2022). Drugs: Felodipine. Available at: https://bnf.nice.org.uk/drug/felodipine.html accessed on 20/04/2022
NICE (2022). Hypertension: Calcium-channel blockers. Available at: https://cks.nice.org.uk/topics/hypertension/prescribing-information/calcium-channel-blockers/ Accessed on 21/04/2022
Ostergren J, Isaksson H, Brodin U, Schwan A, Ohman KP. Effect of amlodipine versus felodipine extended-release on 24-hour ambulatory blood pressure in hypertension. Am J Hypertens. 1998 Jun;11(6 Pt 1):690-6. doi: 10.1016/s0895-7061(98)00032-6. PMID: 9657628. Available at: https://doi.org/10.1016/s0895-7061(98)00032-6 Accessed on 21/04/2022
UKMi (2020). How do amlodipine and felodipine compare for the treatment of hypertension or prophylaxis of stable angina? Available at: https://www.sps.nhs.uk/articles/how-do-amlodipine-and-felodipine-compare-for-the-treatment-of-hypertension-or-prophylaxis-of-stable-angina/ Accessed on 21/04/2022
