Two medicines, side by side
Quinapril vs clonidine
Quinapril and clonidine are both labeled for high blood pressure. Drugs@FDA records approvals of quinapril since 1991 and of clonidine since 1974. In FDA's classes, quinapril is an angiotensin converting enzyme inhibitor and clonidine a central alpha-2 adrenergic agonist.
Check it at the source: the quinapril FDA label on DailyMed (effective December 14, 2023); the clonidine FDA label on DailyMed (effective March 30, 2026).
Highlights of the quinapril record
Quinapril (Accupril) · label of December 14, 2023
FETAL TOXICITY
When pregnancy is detected, discontinue quinapril tablets as soon as possible.
Drugs that act directly on the renin-angiotensin system can cause injury and death to the developing fetus. See WARNINGS : Fetal Toxicity
Used for
From the label: indicationsHypertension Quinapril tablets USP 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. […]
On the market
- Earliest approval on file
- November 19, 1991
- Generic labelers
- 9 labelers
- Pharmacy cost
- Not in the survey
Supply and safety
- Shortage
- In shortage
- Recalls
- 7
Highlights of the clonidine record
Clonidine (Catapres) · label of March 30, 2026
Used for
From the label: indicationsClonidine hydrochloride tablets are indicated in the treatment of hypertension. Clonidine hydrochloride tablets may be employed alone or concomitantly with other antihypertensive agents.
On the market
- Earliest approval on file
- September 3, 1974
- Generic labelers
- 43 labelers
- Pharmacy cost
- $0.0241 per tablet
Supply and safety
- Shortage
- No current entry
- Recalls
- 16
Source: FDA drug labels via openFDA (Quinapril label of December 14, 2023, Clonidine label of March 30, 2026); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do quinapril and clonidine differ on the record?
In FDA's classes, quinapril is an angiotensin converting enzyme inhibitor and clonidine a central alpha-2 adrenergic agonist.
Half-life, in each label's words: Quinapril, “Following multiple oral dosing of quinapril, there is an effective accumulation half-life of quinaprilat of …”; Clonidine, “Following intravenous administration, clonidine displays biphasic disposition with a distribution half-life of about 20 …”
Only the quinapril label carries a boxed warning.
Generics: quinapril since 2004; clonidine since 1986 (Drugs@FDA).
| Quinapril | Clonidine | |
|---|---|---|
| Labeled for | High blood pressure, Heart failure | High blood pressure, ADHD, Pain |
| Pharmacologic class | Angiotensin Converting Enzyme Inhibitor | Central alpha-2 Adrenergic Agonist |
| How it works (label) | n/a | n/a |
| Half-life (label) | Following multiple oral dosing of quinapril, there is an effective accumulation half-life of quinaprilat of approximately 3 hours, and peak plasma quinaprilat concentrations are observed approximately 2 hours post-dose. | Following intravenous administration, clonidine displays biphasic disposition with a distribution half-life of about 20 minutes and an elimination half-life ranging from 12 to 16 hours. |
| Earliest approval on file (Drugs@FDA) | November 19, 1991 | September 3, 1974 |
| First generic approved | December 15, 2004 | July 1, 1986 |
| Generic labelers (NDC) | 9 labelers | 43 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | n/a | $0.0241 per tablet (Clonidine HCl 0.1 mg tablet) |
| 12-month price change | n/a | -3% |
| Boxed warning | Yes | No |
| Shortage now | In shortage | No current entry |
| Recalls recorded | 7 | 16 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 7,842 | 57,116 |
| 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 quinapril
- every medicine labeled for the same conditions