Amlodipine

Overview

What is Amlodipine? 

Amlodipine is a long-acting calcium channel blocker that dilates blood vessels and improves blood flow. It contains amlodipine besylate as its active ingredient, a white crystalline powder slightly soluble in water and sparingly soluble in ethanol. 

Amlodipine is chemically described as 3-Ethyl 5-methyl (±)-2-[(2-aminoethoxy)methyl]-4-(2-chlorophenyl)-1,4-dihydro-6-methyl-3,5-pyridinedicarboxylate, monobenzenesulphonate. It is synthesised through a series of organic reactions involving the creation of the dihydropyridine ring, which is central to its activity. 

Global Name

Generic Name and Brand Names 

• Generic name: Amlodipine
  
• Brand names: Norvasc, Katerzia, Amvasc

Usage

What is Amlodipine used for?

Amlodipine is primarily used to treat: 

• High blood pressure (hypertension) 
• Chest pain (angina) 
• Coronary artery disease 

How do you use Amlodipine?

Availability:

Amlodipine is available in tablets and capsules. 

Dosage information: 

• Adults: 5 mg once daily, with a maximum dose of 10 mg daily. 
• Elderly: Start with the lower dose of 2.5 mg due to increased sensitivity. 
• Children (6-17 years old): 2.5 to 5 mg once daily for hypertension. 
• Pregnancy and Lactation: Consult with your healthcare provider 

Suitable for: 

• Children: Yes, for hypertension, but not for angina. 
• Adults: Yes 
• Elderlies: Yes, with a lower starting dose. 

Who can't take Amlodipine? 

• Children: Not recommended for angina treatment. 
• Adults: Those with severe hypotension or aortic stenosis may need to avoid it. 
• Elderlies: You can take it but start with a lower dose. 
• Pregnancy and Lactation: Use only if advised or prescribed by the doctor.  

Allergies:

Not suitable for individuals with a known hypersensitivity to amlodipine or any excipients of the drug form. 

Warnings and precautions:

Use caution in patients with heart failure or hepatic impairment. 

Amlodipine can be taken with or without food. It is often advised to take the drug at the same time each day. 

Interactions and contraindications:

Amlodipine can interact with other blood pressure medications, certain heart medications, grapefruit and grapefruit juice (for susceptible individuals). 

Side Effects

Common side effects include swelling of ankles or feet, dizziness, and fatigue. Severe side effects may include more significant edema, hypotension, and palpitations. 

Pharmacist Tips

• Storage information: Store at a controlled room temperature between 68-77°F (20-25°C); excursions permitted to 59-86°F (15-30°C). 
• Handling instructions: Handle the medication with clean hands and store it in its original container, away from light and moisture. 

Availability

Where is Amlodipine available in Hong Kong?

Amlodipine is a prescription medication that can be prescribed by healthcare providers.

FAQs

Is Amlodipine available for purchase over the counter?

No, Amlodipine is a prescription medication that a healthcare provider must prescribe.

Can Amlodipine be taken with other blood pressure medications?

Yes, it can be taken with other medications, but always consult your doctor to be advised of potential add-on effects such as hypotension as it may require dose and/or schedule adjustments.

How long does Amlodipine take to lower blood pressure?

Amlodipine starts to lower blood pressure within a few hours of taking it, with the full effect seen in about 7-8 days of regular use.

What should not be taken with Amlodipine?

Avoid taking amlodipine with grapefruit and grapefruit juice and strong CYP3A4 inhibitors (such as ketoconazole), as these can increase the concentration of amlodipine in the blood and heighten the risk of side effects. Always seek medical consult before starting other medications to be properly advised.

When to take Amlodipine? Morning or night?  

Amlodipine can be taken at any time of day, but it's important to take it at the same time every day; some people prefer taking it at night to reduce the risk of any potential side effects like dizziness. Consult with your healthcare provider for personalised advice on when to take Amlodipine.