Hydrochlorothiazide vs. Diltiazem
See how Hydrochlorothiazide and Diltiazem compare on approved uses, dosing, side effects, and cost.
Key Takeaways
Hydrochlorothiazide and diltiazem both lower blood pressure but work through different mechanisms — one removes excess fluid, the other relaxes blood vessels and slows the heart.
Diltiazem also treats angina and abnormal heart rhythms, while hydrochlorothiazide's approved uses are limited to blood pressure and fluid retention.
Hydrochlorothiazide is typically far less expensive, while diltiazem requires a multi-week dose titration that hydrochlorothiazide does not.
Hydrochlorothiazide vs. Diltiazem Drug Summary
Hydrochlorothiazide
Hydrochlorothiazide is a thiazide diuretic used to treat high blood pressure and fluid buildup from conditions like heart failure or liver disease. It works by helping the kidneys remove excess salt and water. It's taken as a once-daily tablet or capsule, alone or combined with other blood pressure medicines.
Diltiazem
Diltiazem is a non-dihydropyridine calcium channel blocker used to treat high blood pressure, angina, and certain fast heart rhythms. It relaxes blood vessels and slows the heart rate to reduce the heart's workload. It comes in immediate-release, extended-release, and IV forms, with oral tablets typically taken once daily.
Hydrochlorothiazide vs. Diltiazem Side Effects
Hydrochlorothiazide
Diltiazem
Hydrochlorothiazide vs. Diltiazem Dosage
Hydrochlorothiazide
Diltiazem
| STAGE | DOSE | WHEN |
| Starting dose | 25 mg once daily | At the start |
| Maximum dose | 25-100 mg once daily | If needed |
| Dose changes | 2 increases | As tolerated |
| STAGE | DOSE | WHEN |
| Starting dose | 120-240 mg once daily | Weeks 1-2 |
| Maximum dose | 540 mg once daily | If needed |
| Dose changes | 5 increases | As tolerated |
Hydrochlorothiazide
| STAGE | DOSE | WHEN |
| Starting dose | 25 mg once daily | At the start |
| Maximum dose | 25-100 mg once daily | If needed |
| Dose changes | 2 increases | As tolerated |
Diltiazem
| STAGE | DOSE | WHEN |
| Starting dose | 120-240 mg once daily | Weeks 1-2 |
| Maximum dose | 540 mg once daily | If needed |
| Dose changes | 5 increases | As tolerated |
Hydrochlorothiazide vs. Diltiazem Indications
Hydrochlorothiazide
Hydrochlorothiazide is FDA-approved to manage hypertension, either alone or alongside other blood pressure medications. It's also approved for treating edema caused by heart failure, cirrhosis, kidney disease, or steroid and estrogen therapy. Off-label, it's sometimes used to prevent calcium-based kidney stones.
Lowers blood pressure alone or with other antihypertensives
Treats fluid retention from heart failure, cirrhosis, or kidney disease
Treats edema from corticosteroid or estrogen therapy
Off-label: helps prevent calcium kidney stones
Diltiazem
Diltiazem is FDA-approved to treat hypertension, chronic stable angina, and Prinzmetal's (vasospastic) angina. It's also approved to control heart rate in atrial fibrillation, atrial flutter, and paroxysmal supraventricular tachycardia. Off-label, it's sometimes used for migraine prevention or Raynaud's phenomenon.
Lowers blood pressure as monotherapy or combination therapy
Treats chronic stable and vasospastic (Prinzmetal's) angina
Controls heart rate in atrial fibrillation and flutter
Treats paroxysmal supraventricular tachycardia (PSVT)
Hydrochlorothiazide vs. Diltiazem Pros and Cons
Hydrochlorothiazide
Hydrochlorothiazide has decades of safety data and a simple once-daily dose that doesn't require titration. It's one of the least expensive blood pressure medications available, though it can cause electrolyte shifts that need periodic monitoring.
Pros
Decades of established real-world safety data
Simple once-daily dosing with no titration needed
Roughly $4 to $35 per month without insurance, notably cheaper than diltiazem
Often combined with other antihypertensives in single-pill combos
Cons
Can cause electrolyte imbalances that need monitoring
Increases skin cancer risk with long-term cumulative use
Not approved for angina or heart rhythm problems
Not recommended for use during pregnancy
Diltiazem
Diltiazem offers broader use beyond blood pressure, including angina and heart rhythm control, with both oral and IV formulations. It requires a gradual titration schedule and carries more cardiac contraindications, and it typically costs more than hydrochlorothiazide.
Pros
Also treats angina and controls heart rate in atrial fibrillation
Available as an IV infusion for urgent rate control
Multiple extended-release formulations allow flexible dosing
Off-label uses for migraine prevention and Raynaud's phenomenon
Cons
Requires gradual dose titration over several weeks
Contraindicated in certain heart block and sick sinus syndrome
Can worsen heart failure in patients with ventricular dysfunction
Roughly $18 to $125 per month without insurance, pricier than hydrochlorothiazide
Common Symptoms and Related Diseases You Can Explore
Explore a range of common symptoms the Doctronic Symptom Checker can help you understand.