Skip to main content

What the FDA labels say about taking them together

Lanthanum and tecovirimat

Tecovirimat's FDA label of December 31, 2025 names lanthanum in its drug interactions section; the lanthanum label PlainMeds reads does not name tecovirimat. The tecovirimat label: “Monitor for signs or symptoms of adverse effects when TPOXX is co-administered with phosphate binders.”

Check it at the source: the lanthanum FDA label on DailyMed (effective December 31, 2024, Takeda Pharmaceuticals America, Inc.); the tecovirimat FDA label on DailyMed (effective December 31, 2025, SIGA Technologies, Inc.).

What does the lanthanum label say about tecovirimat?

Lanthanum's label (effective December 31, 2024) does not name tecovirimat in these sections. A label lists what its studies and reports found; it is not a complete list.

Source: FDA drug label (Fosrenol), Takeda Pharmaceuticals America, Inc., effective December 31, 2024 (SPL set f10776b2-2c25-4343-aabe-68f302e5cb54), via openFDA; the full label on DailyMed

What does the tecovirimat label say about lanthanum?

Tecovirimat label, drug interactions

Concomitant Drug Class/Drug Name: Calcium acetate Lanthanum carbonate Sevelamer carbonate Sucroferric oxyhydroxide; Effect on Concentration a: ↑ tecovirimat; Clinical Effect/Recommendation: Monitor for signs or symptoms of adverse effects when TPOXX is co-administered with phosphate binders [see Overdose ()].

Source: FDA drug label (TPOXX), SIGA Technologies, Inc., effective December 31, 2025 (SPL set fce826ab-4d6a-4139-a2ee-a304a913a253), 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

5Lanthanum generic labelers
0Tecovirimat generic labelers
LanthanumTecovirimat
Labeled forn/an/a
Boxed warningNoNo
Pharmacy cost (NADAC)$3.15 per tablet 1,000 mg tablet chwn/a
Shortage nowNo current entryNo 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?