What the FDA labels say about taking them together
Isosorbide dinitrate and tadalafil
Isosorbide dinitrate's FDA label of March 2, 2020 names tadalafil in its contraindications section; tadalafil's label does not name isosorbide dinitrate itself but warns about its class (nitrate vasodilators). The isosorbide dinitrate label: “Do not use Isosorbide Dinitrate in patients who are taking certain drugs for erectile dysfunction, such as sildenafil, tadalafil, or vardenafil.”
Check it at the source: the isosorbide dinitrate FDA label on DailyMed (effective March 2, 2020, Oceanside Pharmaceuticals); the tadalafil FDA label on DailyMed (effective June 3, 2026, Eli Lilly and Company).
What does the isosorbide dinitrate label say about tadalafil?
Isosorbide dinitrate label, contraindicationsDo not use Isosorbide Dinitrate in patients who are taking certain drugs for erectile dysfunction (phosphodiesterase inhibitors), such as sildenafil, tadalafil, or vardenafil.
Source: FDA drug label (Isosorbide Dinitrate), NDA012093 (Bausch), as published by Oceanside Pharmaceuticals, effective March 2, 2020 (SPL set 723d9f78-9d77-4575-af27-1aa117e6b8d7), via openFDA; the full label on DailyMed
What does the tadalafil label say about isosorbide dinitrate?
Tadalafil's label does not name isosorbide dinitrate itself; it warns about its class (nitrate vasodilators):
Tadalafil label, contraindicationsCONTRAINDICATIONS Administration of CIALIS to patients using any form of organic nitrate is contraindicated.
Tadalafil label, contraindicationsAdministration of CIALIS to patients who are using any form of organic nitrate, either regularly and/or intermittently, is contraindicated.
Source: FDA drug label (Cialis), Eli Lilly and Company, effective June 3, 2026 (SPL set bcd8f8ab-81a2-4891-83db-24a0b0e25895), 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
| Isosorbide dinitrate | Tadalafil | |
|---|---|---|
| Labeled for | Angina | Erectile dysfunction, Enlarged prostate (BPH), Pulmonary arterial hypertension |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $0.154 per tablet 10 mg tablet | $0.167 per tablet 20 mg tablet |
| 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