What the FDA labels say about taking them together
Colestipol and penicillin g
Colestipol's FDA label of February 19, 2024 names penicillin g in its drug interactions section; the penicillin g labels PlainMeds reads (2) do not name colestipol. The colestipol label: “The absorption of tetracycline, furosemide, penicillin G, hydrochlorothiazide and gemfibrozil was significantly decreased when given simultaneously with colestipol hydrochloride; …”
Check it at the source: the colestipol FDA label on DailyMed (effective February 19, 2024, Zydus Pharmaceuticals USA Inc.); the penicillin g FDA label on DailyMed (effective September 16, 2020, Sandoz Inc).
What does the colestipol label say about penicillin g?
Colestipol label, drug interactionsThe absorption of tetracycline, furosemide, penicillin G, hydrochlorothiazide and gemfibrozil was significantly decreased when given simultaneously with colestipol hydrochloride; these drugs were not tested to determine the effect of administration 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
What does the penicillin g label say about colestipol?
Penicillin g's label (effective September 16, 2020) and its 1 other brand-application label do not name colestipol in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Penicillin G Potassium), Sandoz Inc, effective September 16, 2020 (SPL set 91950983-4884-40d1-abd8-bcc953d61b7f), 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
| Colestipol | Penicillin g | |
|---|---|---|
| Labeled for | High cholesterol | Bacterial infections |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $0.658 per tablet 1 g tablet | n/a |
| Shortage now | No current entry | 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