What the FDA labels say about taking them together
Dexamethasone and pembrolizumab
Pembrolizumab's FDA label of July 10, 2026 names dexamethasone in its warnings and precautions section; the dexamethasone labels PlainMeds reads (4) do not name pembrolizumab. The pembrolizumab label: “… or PD-L1 blocking antibody in combination with a thalidomide analogue plus dexamethasone is not recommended outside of controlled clinical trials. Embryo-Fetal toxicity:”
Check it at the source: the dexamethasone FDA label on DailyMed (effective June 6, 2025, Hikma Pharmaceuticals USA, Inc.); the pembrolizumab FDA label on DailyMed (effective July 10, 2026, Merck Sharp & Dohme LLC).
What does the dexamethasone label say about pembrolizumab?
Dexamethasone's label (effective June 6, 2025) and its 3 other brand-application labels do not name pembrolizumab in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Dexamethasone Intensol), Hikma Pharmaceuticals USA, Inc., effective June 6, 2025 (SPL set b15200fb-1826-472b-a907-e677a272513b), via openFDA; the full label on DailyMed
What does the pembrolizumab label say about dexamethasone?
Pembrolizumab label, warnings and precautionsFatal and other serious complications can occur in patients who receive allogeneic HSCT before or after being treated with a PD-1/PD-L1 blocking antibody. ( 5.3 ) Treatment of patients with multiple myeloma with a PD-1 or PD-L1 blocking antibody in combination with a thalidomide analogue plus dexamethasone is not recommended outside of controlled clinical trials. ( 5.4 ) Embryo-Fetal toxicity:
Source: FDA drug label (KEYTRUDA), Merck Sharp & Dohme LLC, effective July 10, 2026 (SPL set 9333c79b-d487-4538-a9f0-71b91a02b287), 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
| Dexamethasone | Pembrolizumab | |
|---|---|---|
| Labeled for | Asthma, Eczema (atopic dermatitis), Leukemia, lymphoma and myeloma, Herpes and shingles, Crohn's disease and ulcerative colitis, Multiple sclerosis, Osteoarthritis, Rheumatoid arthritis, Psoriasis, Allergies, Anemia, Pain | Lung cancer, Colorectal cancer, Leukemia, lymphoma and myeloma, Breast cancer |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $0.193 per tablet 4 mg tablet | n/a |
| Shortage now | In shortage | 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