Diltiazem
Diltiazem is a calcium channel blocker used for high blood pressure, some angina types, and certain heart rhythm problems when prescribed. Capsules and tablets come in immediate and prolonged-release forms — use only the formulation on your prescription.
This medicine is part of the Blood pressure, cholesterol & related category.
Generic name: diltiazem
Quick answers
Short replies to searches people often run before speaking to a clinician. For the overview of what the medicine is used for, see the short summary under the page title above.
What is it for?
Diltiazem is a calcium channel blocker used for high blood pressure, some angina types, and certain heart rhythm problems when prescribed.
How long does it take to work?
Blood pressure can fall over days to weeks after starting or changing dose; attend follow-up checks your GP arranges.
What are common side effects?
Headache, flushing, ankle swelling, dizziness, slow pulse, or constipation may occur.
Can you take paracetamol or ibuprofen with it?
Ask your GP or pharmacist before taking Diltiazem with paracetamol or ibuprofen. Many adults use paracetamol for short periods when appropriate; NSAIDs such as ibuprofen need extra checks with your other medicines and health conditions.
More about what Diltiazem is used for
Diltiazem is a calcium channel blocker used for high blood pressure, some angina types, and certain heart rhythm problems when prescribed.
Capsules and tablets come in immediate and prolonged-release forms — use only the formulation on your prescription.
How does Diltiazem work, and how long does it take to work?
It relaxes arteries and can slow conduction through the AV node, lowering blood pressure and sometimes heart rate.
Onset and duration depend on the specific product.
How and when should you take Diltiazem?
Follow your leaflet for whether to take with food and whether tablets may be split. Prolonged-release products must often be swallowed whole.
Do not substitute brands without pharmacist check — strengths may differ.
What are the common side effects of Diltiazem?
Headache, flushing, ankle swelling, dizziness, slow pulse, or constipation may occur.
Serious side effects of Diltiazem — when to get urgent help
Seek urgent help for fainting, severe bradycardia symptoms, or sudden breathlessness.
Severe skin reactions are rare but need prompt medical care.
What if you miss a dose of Diltiazem?
Take when remembered unless nearly time for next; do not double.
Who should not take Diltiazem?
Some heart blocks without pacing, sick sinus syndrome, severe hypotension, and acute heart failure in selected cases need alternatives.
Pregnancy and breastfeeding need individual advice.
Can you take paracetamol or ibuprofen with Diltiazem? — other interactions
Beta-blockers increase conduction risks. Diltiazem raises levels of some statins and Dabigatran — your prescriber adjusts doses.
Diltiazem in pregnancy and breastfeeding
Discuss with your prescriber before use in pregnancy or breastfeeding.
Blood tests and monitoring on Diltiazem
Blood pressure, pulse, and occasional blood tests may be arranged.
What might your GP prescribe instead of Diltiazem?
Verapamil, Amlodipine, or beta-blockers may be considered for similar indications.
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Frequently asked questions about Diltiazem
People also ask — common Google searches
- What is Diltiazem used for?
- Diltiazem is a calcium channel blocker used for high blood pressure, some angina types, and certain heart rhythm problems when prescribed. Capsules and tablets come in immediate and prolonged-release forms — use only the formulation on your prescription.
- How long does Diltiazem take to work?
- Blood pressure can fall over days to weeks after starting or changing dose; attend follow-up checks your GP arranges. Always follow your prescriber’s follow-up plan.
- Can you take Diltiazem with paracetamol or ibuprofen?
- Ask your GP or pharmacist before taking Diltiazem with Paracetamol or Ibuprofen. Many adults use paracetamol for short periods when appropriate; NSAIDs such as ibuprofen need extra checks with your other medicines and health conditions.
- What are the side effects of Diltiazem?
- Headache, flushing, ankle swelling, dizziness, slow pulse, or constipation may occur. See the sections below for more detail, including serious side effects and when to seek urgent help.
- Does diltiazem cause ankle swelling?
- Calcium channel blockers can cause ankle oedema. If swelling is new or one-sided, seek medical review to rule out clots or heart failure worsening.
- Can I drink grapefruit juice with diltiazem?
- Grapefruit can increase diltiazem levels. It is sensible to avoid regular large amounts unless your clinician has said otherwise.
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Often used with
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