Cyclophosphamide and Tipranavir: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Tipranavir
Cyclophosphamide
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
Increased risk of chemotherapy-induced mucositis, neutropenia, and infection
Interaction Deep Dive
Concomitant use of cyclophosphamide with a protease inhibitor (PI) may increase the concentration of cytotoxic metabolites and increase the incidence of infection, neutropenia, or mucositis1, possibly due to competitive inhibition of CYP metabolism of cyclophosphamide or inhibition of the P-glycoprotein efflux pump by PIs 2. During a drug-interaction study in patients with AIDS-related non-Hodgkin lymphoma, PI-based HAART regimens plus cyclosporine/docetaxel/etoposide (CDE) were associated with a significantly higher incidence rate of infection and neutropenia compared with a PI-sparing HAART plus CDE regimen. Use caution when coadministering cyclophosphamide and a PI, and closely monitor patients for cyclophosphamide-associated adverse effects or consider alternative antiretroviral therapy to PIs 2
Why it happens (mechanism)
Unknown
Literature reports
1 report — tap to read
a) During a drug-interaction study of patients recently diagnosed with AIDS-related non-Hodgkin lymphoma, administration of protease inhibitor-based (PI-based) HAART and cyclophosphamide/docetaxel/etoposide (CDE) resulted in increased incidences of chemotherapy-induced infection and neutropenia compared with PI-sparing HAART and CDE over 190 total cycles. Grade 3 or 4 infections requiring hospitalization were reported in significantly more patients administered PI-based HAART plus CDE (n=48; 48% vs 25%) compared with those treated with PI-sparing HAART plus CDE regimens (n=142), a similar significant difference was seen with Grade 4 neutropenia (54% and 38%). Day 10 and day 14 median neutrophil counts were significantly lower in patients who received concomitant PI-based HAART compared with patients who received concomitant PI-sparing HAART during CDEt 2.
Common questions
Can I take Cyclophosphamide and Tipranavir together?
Increased risk of chemotherapy-induced mucositis, neutropenia, and infection Always confirm with your pharmacist or prescriber before making any change.
How serious is the Cyclophosphamide and Tipranavir interaction?
It is rated major. Potentially serious — often needs a change or close 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 "established". Well documented — supported by controlled studies or strong clinical data.
Questions for your pharmacist
- Does my dose of Cyclophosphamide or Tipranavir 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 a safer alternative to one of these medications for me?
References (2)
- Product Information: CYCLOPHOSPHAMIDE intravenous injection, oral tablets, cyclophosphamide intravenous injection, oral tablets. Baxter Healthcare Corporation (per FDA), Deerfield, IL, 2013. DailyMed
- Bower M, McCall-Peat N, Ryan N, et al: Protease inhibitors potentiate chemotherapy-induced neutropenia. Blood 2004; 104(9):2943-2946. PubMed
Keep reading about Tipranavir
Keep reading about Cyclophosphamide
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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