What the FDA labels say about taking them together
Chlorothiazide and colestipol
Chlorothiazide's FDA label (Diuril) of November 1, 2021 names colestipol in its drug interactions section, and colestipol's label names chlorothiazide too. The colestipol label: “Studies in humans show that the absorption of chlorothiazide as reflected in urinary excretion is markedly decreased even when administered one hour before colestipol hydrochloride.”
Check it at the source: the chlorothiazide FDA label on DailyMed (effective August 4, 2026, Sagent Pharmaceuticals); the colestipol FDA label on DailyMed (effective February 19, 2024, Zydus Pharmaceuticals USA Inc.).
What does the chlorothiazide label say about colestipol?
Diuril label (Salix Pharmaceuticals, Inc, November 1, 2021), drug interactionsCholestyramine and Colestipol Resins - Both cholestyramine and colestipol resins have the potential of binding thiazide diuretics and reducing diuretic absorption from the gastrointestinal tract.
Source: FDA drug label (Diuril, NDA011870), Salix Pharmaceuticals, Inc, effective November 1, 2021 (SPL set bd936e35-1af8-42da-bcc0-f22489d68574), via openFDA
Source: FDA drug label (chlorothiazide sodium), Sagent Pharmaceuticals, effective August 4, 2026 (SPL set 82dd0bdd-e6bd-48ea-8f58-c8bf71bbfe2c), via openFDA; the full label on DailyMed
What does the colestipol label say about chlorothiazide?
Colestipol label, drug interactionsStudies in humans show that the absorption of chlorothiazide as reflected in urinary excretion is markedly decreased even when administered one hour before colestipol hydrochloride.
Source: FDA drug label (Colestipol hydrochloride), Zydus Pharmaceuticals USA Inc., effective February 19, 2024 (SPL set 71f12e0d-373a-4867-b37c-f24d99c5ce95), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Chlorothiazide | Colestipol | |
|---|---|---|
| Labeled for | Heart failure, Edema (fluid retention), High blood pressure | High cholesterol |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | n/a | $0.658 per tablet 1 g tablet |
| Shortage now | A presentation being discontinued | No current entry |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once