Two medicines, side by side
Prazosin vs losartan
Prazosin and losartan are both labeled for high blood pressure. Drugs@FDA records approvals of prazosin since 1976 and of losartan since 1995. Pharmacies paid $0.0842 per prazosin 1 mg capsule and $0.0327 per losartan potassium 50 mg tablet (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like. In FDA's classes, prazosin is an alpha-adrenergic blocker and losartan an angiotensin 2 receptor blocker.
Check it at the source: the prazosin FDA label on DailyMed (effective March 6, 2026); the losartan FDA label on DailyMed (effective January 20, 2026).
Highlights of the prazosin record
Prazosin (Minipress) · label of March 6, 2026
Used for
From the label: indicationsPrazosin hydrochloride capsules are indicated for the treatment of hypertension, to lower blood pressure. Lowering blood pressure reduces the risk of fatal and nonfatal cardiovascular events, primarily strokes and myocardial infarctions. These benefits have been seen in controlled trials of antihypertensive drugs from a wide variety of pharmacologic classes, including this drug. […]
On the market
- Earliest approval on file
- June 23, 1976
- Generic labelers
- 33 labelers
- Pharmacy cost
- $0.0842 per capsule
Supply and safety
- Shortage
- A presentation being discontinued
- Recalls
- 10
Highlights of the losartan record
Losartan (Cozaar) · label of January 20, 2026
FETAL TOXICITY When pregnancy is detected, discontinue COZAAR as soon as possible. Drugs that act directly on the renin-angiotensin system can cause injury and death to the developing fetus [see Warnings and Precautions (5.1) ]. WARNING: FETAL TOXICITY See full prescribing information for complete boxed warning. When pregnancy is detected, discontinue COZAAR as soon as possible. Drugs that act directly on the renin-angiotensin system can cause injury and death to the developing fetus.
Used for
From the label: indicationsCOZAAR is an angiotensin II receptor blocker (ARB) indicated for: Treatment of hypertension, to lower blood pressure in adults and children greater than 6 years old. Lowering blood pressure reduces the risk of fatal and nonfatal cardiovascular events, primarily strokes and myocardial infarctions. ( 1.1 ) Reduction of the risk of stroke in patients with hypertension and left ventricular hypertrophy. […]
On the market
- Earliest approval on file
- April 14, 1995
- Generic labelers
- 43 labelers
- Pharmacy cost
- $0.0327 per tablet
Supply and safety
- Shortage
- No current entry
- Recalls
- 77
Source: FDA drug labels via openFDA (Prazosin label of March 6, 2026, Losartan label of January 20, 2026); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do prazosin and losartan differ on the record?
In FDA's classes, prazosin is an alpha-adrenergic blocker and losartan an angiotensin 2 receptor blocker.
Only the losartan label carries a boxed warning.
Generics: prazosin since 1988; losartan since 2010 (Drugs@FDA).
| Prazosin | Losartan | |
|---|---|---|
| Labeled for | High blood pressure | High blood pressure, Chronic kidney disease, Stroke prevention |
| Pharmacologic class | alpha-Adrenergic Blocker | Angiotensin 2 Receptor Blocker |
| How it works (label) | n/a | Angiotensin II [formed from angiotensin I in a reaction catalyzed by angiotensin converting enzyme (ACE, kininase II)] is a potent vasoconstrictor, the primary vasoactive hormone of the renin-angiotensin system, and an important component … |
| Half-life (label) | n/a | The terminal half-life of losartan is about 2 hours and of the metabolite is about 6-9 hours. |
| Earliest approval on file (Drugs@FDA) | June 23, 1976 | April 14, 1995 |
| First generic approved | September 12, 1988 | April 6, 2010 |
| Generic labelers (NDC) | 33 labelers | 43 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $0.0842 per capsule (Prazosin 1 mg capsule) | $0.0327 per tablet (Losartan potassium 50 mg tablet) |
| 12-month price change | -20% | +2% |
| Boxed warning | No | Yes |
| Shortage now | A presentation being discontinued | No current entry |
| Recalls recorded | 10 | 77 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 7,384 | 200,566 |
| DEA schedule | none | none |
Source: Drugs@FDA, FDA NDC Directory, CMS NADAC of October 7, 2026, FDA shortages and recalls, FAERS via openFDA (FDA files October 8, 2026)
What next?
- Alternatives to prazosin
- every medicine labeled for the same conditions