Diltiazem

Diltiazem is a prescription calcium channel blocker used to treat conditions affecting heart rate, rhythm, or blood pressure. Doctors commonly prescribe Diltiazem to manage high blood pressure (hypertension), chronic chest pain (angina), and certain abnormal heart rhythms like atrial flutter or atrial fibrillation (AFib). In addition to lowering blood pressure, Diltiazem also affects how electrical signals move through the heart.

This makes it especially useful for patients who need both blood pressure control and heart rate management. Diltiazem has been used in clinical practice for several decades and is available in multiple formulations, including immediate-release and extended-release oral products. However, this page focuses on Diltiazem immediate-release tablets. Note that both immediate-release and extended-release formulations lower blood pressure, but extended-release formulations are commonly used for long-term hypertension management. Speak with your medical provider before starting treatment to choose the right medication form.

Diltiazem is FDA-approved to manage:

• Hypertension
• Chronic stable angina
• Certain atrial arrhythmias (AFib, atrial flutter)

Diltiazem belongs to a class of calcium channel blockers that work by blocking calcium from entering heart and blood vessel cells. Calcium is important for muscle contraction. By reducing calcium entry:

• Blood vessels relax and widen, helping reduce blood pressure.
• The heart beats more slowly and efficiently.
• The oxygen demand of the heart muscle decreases, easing angina symptoms.

Some patients may see changes in blood pressure or heart rate within a few days, while full effects can take several weeks.

The choice between IR and ER diltiazem depends on the condition being treated, patient response, and provider judgment. Always take the prescribed formulation.

These side effects are commonly reported by users. They are mild and usually resolve on their own, but if they last more than a few days, tell your doctor right away.

• Headache
• Dizziness
• Swelling of the ankles or feet
• Fatigue
• Flushing or warmth of the face
• Constipation
• Nausea
• Nasal congestion

What Are Serious Side Effects of Diltiazem (When to Seek Help)?

Contact your doctor immediately if you experience:

• Very slow heart rate (bradycardia)
• Heart block
• Severe low blood pressure
• Worsening heart failure
• Liver injury
• Severe allergic reactions

The best time of day to take Diltiazem depends on the specific form you are prescribed and the condition being treated. Never adjust the timing or dose on your own. Sudden changes can lead to heart rhythm problems, blood pressure changes, or worsening chest pain.

• Extended-Release Diltiazem: This formulation is taken once daily and can be taken in the morning or evening, as your doctor has instructed.
• Immediate-Release Diltiazem: IR tablets are typically taken two to four times daily, spaced evenly. The tablets can be taken before meals and at bedtime unless your doctor advises otherwise.

Taking Diltiazem With or Without Food

• Diltiazem can be taken with or without food.
• Taking the medication with food helps prevent stomach upset.
• Swallow tablets or capsules whole with water.
• Take doses at the same time each day for consistent heart control.
• Do not stop Diltiazem suddenly without medical advice.

Dosage may vary depending on the condition, formulation, and patient response. Before taking Diltiazem for angina, hypertension, or AFib, talk to your doctor. They will prescribe the appropriate formulation and dosage based on your condition.

• Immediate-release (IR) is generally taken 3–4 times per day.
• Extended-release (ER) is usually taken once daily, often in the morning or evening.
• Always follow your healthcare provider’s instructions, as individual doses may differ.

Yes, Losartan and Diltiazem can be taken together if your doctor approves, and this combination is commonly prescribed to people who have high blood pressure along with heart rate or chest pain concerns. When used correctly and under a healthcare provider's supervision, the combination is generally safe.

Losartan is an angiotensin II receptor blocker (ARB) that relaxes blood vessels and lowers blood pressure. Diltiazem is a calcium channel blocker that lowers blood pressure and slows the heart rate. Using them together can improve blood pressure control without relying on high doses of a single medication.

Like other calcium channel blockers, Diltiazem carries certain risks. Understanding these risks can help prevent adverse reactions.

Who Should Not Take Diltiazem?

Do not use Diltiazem for angina or AFib if you have:

• Sick sinus syndrome without a pacemaker.
• Second- or third-degree AV block without a pacemaker.
• Severe hypotension (low blood pressure).
• Acute myocardial infarction with pulmonary congestion.
• Known hypersensitivity to Diltiazem.

Diltiazem Warnings and Precautions

Patients using Diltiazem for AFib or angina must use it cautiously due to its effects on heart rate, blood pressure, and liver metabolism.

• This medication can cause bradycardia (slow heart rate) or heart block, especially when combined with beta-blockers.
• Worsening heart failure may occur in some patients with reduced ventricular function.
• While rare, liver enzyme elevations and liver injury have been reported with the use of Diltiazem heart medication. Talk to your provider before starting treatment with this medication.
• This medication may sometimes drop blood pressure too much, leading to dizziness or fainting. Patients with hypotension should use it cautiously.
• Elderly patients using Diltiazem for AFib or chest pain may be more sensitive to the medication’s effects. Use carefully in such patients.
• Do not stop treatment suddenly, as abrupt discontinuation may worsen angina symptoms. Consult a doctor before discontinuing or changing your dose.
• There are no well-controlled studies or enough information on pregnant or breastfeeding women. Use this medication only if the benefits are higher than the potential risks.

Diltiazem and beta-blockers can be used together, but this combination requires caution and close medical supervision. It is not routinely avoided, but it is also not suitable for every patient. Diltiazem, a calcium channel blocker, and beta-blockers both affect the heart, but in different ways:

Diltiazem slows electrical conduction through the heart and relaxes blood vessels. Meanwhile, beta-blockers reduce heart rate and blood pressure, and attenuate the heart’s response to stress hormones. Doctors may prescribe the combination for:

• Atrial fibrillation or other supraventricular arrhythmias when single-drug therapy does not adequately control heart rate.
• Angina in selected patients who need additional symptom control.

Since Diltiazem is taken multiple times, the rules of missed doses might differ. If you are taking:

• Once daily: Take it as soon as possible unless it is less than 12 hours until your next dose.
• Twice daily: Take the missed dose when you remember, unless it is less than 4 hours until your next dose.

Thrice daily: Take your next dose according to your regular dosing schedule.

Taking too much Diltiazem can be dangerous and requires immediate medical attention. In case of an overdose, call Poison Control at 1-800-222-1222 right away. Possible Diltiazem overdose symptoms may include:

• Very slow or irregular heartbeat
• Severe low blood pressure
• Dizziness
• Confusion
• Fainting
• Shortness of breath
• Extreme fatigue

Diltiazem can affect heart rate and blood pressure. Combining it with other medications may cause adverse reactions. While some combinations should be avoided, others require close monitoring. Here are some drugs that may interact with Diltiazem:

Strictly Avoid

• Certain Antiarrhythmic Drugs:
  • Ivabradine
  • Disopyramide
• Drugs That Significantly Slow Heart Conduction:
  • Sotalol

Use with Caution

• Beta-Blockers:
  • Metoprolol
  • Atenolol
  • Propranolol
• Statins:
  • Lovastatin
  • Atorvastatin
  • Simvastatin
• Immunosuppressants & Transplant Drugs:
  • Cyclosporine
  • Tacrolimus
• Psychiatric Medications:
  • Carbamazepine
  • Buspirone
  • Midazolam
  • Triazolam

Your healthcare provider chooses an alternative based on your heart rhythm, blood pressure goals, and other medical conditions:

• For Atrial Fibrillation or Supraventricular Arrhythmias:
  • Metoprolol
  • Atenolol
  • Propranolol
  • Carvedilol
• For High Blood Pressure:
  • Lisinopril
  • Enalapril
  • Losartan
  • Valsartan
  • Amlodipine
  • Nifedipine
• For Chronic Stable Angina:
  • Amlodipine
  • Isosorbide mononitrate
  • Ranolazine

Long-term treatment for heart or blood pressure conditions can be costly for some patients. That’s why some U.S. patients choose to buy Diltiazem online from Canada, where low-cost options are available. Diltiazem IR and Diltiazem ER are lower-cost generics.

Polar Bear Meds can further help you save over 90% as compared to typical U.S. pharmacy rates. When you order Diltiazem from Canada through our network of licensed Canadian pharmacies, you get quality medications at competitive pricing. We dispense Diltiazem tablets only with a valid prescription from a qualified doctor and follow rigorous safety checks on all medications.

By using our Diltiazem coupon, you can:

• Access lower-cost generic medications without sacrificing quality.
• Get 10% off on your first order.
• Avoid high retail pharmacy prices.
• Continue prescribed treatment consistently without financial strain.
• Receive your package within 3–5 business days via Xpress Post.

Cost savings can vary depending on dosage, formulation, and supply length. Always compare options and consult your healthcare provider or pharmacist if you have questions about switching pharmacies.

• https://www.mayoclinic.org/drugs-supplements/diltiazem-oral-route/description/drg-20071775
• https://www.accessdata.fda.gov/drugsatfda_docs/label/2010/020062s040lbl.pdf
• https://www.nhs.uk/medicines/diltiazem/how-and-when-to-take-diltiazem/
• https://labeling.pfizer.com/ShowLabeling.aspx?id=12797