Lanthanum and Cysteamine: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Lanthanum
Cysteamine
No brand names on record
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Altered cysteamine pharmacokinetics and increased WBC cystine concentration
Interaction Deep Dive
Concomitant administration of cysteamine and this drug may result in altered cysteamine pharmacokinetics and increased WBC cystine concentration. Give cysteamine 1 hour before or 1 hour after this drug1.
Why it happens (mechanism)
Unknown
Common questions
Can I take Lanthanum and Cysteamine together?
Altered cysteamine pharmacokinetics and increased WBC cystine concentration Always confirm with your pharmacist or prescriber before making any change.
How serious is the Lanthanum and Cysteamine interaction?
It is rated moderate. Can be significant — usually manageable with monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
Questions for your pharmacist
- Does my dose of Lanthanum or Cysteamine need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there anything you'd monitor while I'm on both?
References (1)
- Product Information: PROCYSBI(R) oral delayed release capsules, cysteamine bitartrate oral delayed release capsules. Horizon Pharma USA, Inc. (per manufacturer), Lake Forest, IL, 2017. DailyMed
Keep reading about Lanthanum
Keep reading about Cysteamine
Check another combination
Our instant two-drug interaction checker is almost here.
Still have questions about this combination?
Every question gets a real answer from a licensed pharmacist — free, and usually within a day.
Ask the pharmacist