From the Guidelines
Cyclophosphamide (CPM) has potential drug interactions, particularly with agents that inhibit or induce its metabolism, such as CYP3A4 inhibitors.
Key Interactions
- Aprepitant: The concomitant administration of aprepitant with CPM may theoretically decrease the clearance of CPM, resulting in prolonged exposure and toxicity, or decreased exposure to its active metabolite 1.
- Docetaxel: Aprepitant has been shown to have no clinically significant effect on docetaxel pharmacokinetics or toxicity when co-administered with CPM 1.
Clinical Implications
- The incidence of febrile neutropenia was identical in aprepitant- and placebo-treated patients, suggesting that the exposure to CPM was comparable 1.
- Aprepitant reduced the exposure to the active metabolite of CPM by 5%, but inhibitory concentrations remained in the therapeutic range in the presence of aprepitant in a human liver microsome system 1.
Precautions
- Monitoring: Patients receiving CPM with potential interacting medications should be closely monitored for adverse effects and toxicity.
- Dose Adjustments: Dose adjustments may be necessary to minimize the risk of adverse interactions, although the exact adjustments are not specified in the available evidence.
From the Research
Cyclophosphamide (CPM) Drug Interactions
There are no research papers provided that directly discuss Cyclophosphamide (CPM) drug interactions. The studies provided focus on drug interactions involving selective serotonin reuptake inhibitors (SSRIs), monoamine oxidase inhibitors (MAOIs), and other antidepressants.
Relevant Information on Drug Interactions
While not directly related to Cyclophosphamide, the studies provide information on potential drug interactions that may be relevant in a broader context:
- Selective serotonin reuptake inhibitors (SSRIs) are involved in many drug interactions with potentially serious clinical consequences 2.
- Combining SSRIs with other psychotropics, especially MAOIs and tricyclic antidepressants, can lead to serotonin syndrome 2, 3.
- Tramadol can be safely combined with antidepressants, but monitoring and counseling patients are prudent when starting a new serotonergic agent or when doses are increased 4.
- Newer antidepressants have a relatively low risk for pharmacodynamic drug interactions, but may be susceptible to pharmacokinetic drug interactions 5.
- Classic MAOIs, such as phenelzine, tranylcypromine, and isocarboxazid, have specific drug-drug interactions and side-effect management considerations 6.
Key Points to Consider
- Drug interactions can have serious clinical consequences, and it is essential to consider potential interactions when prescribing medications.
- Combining certain medications, such as SSRIs and MAOIs, can increase the risk of serotonin syndrome.
- Monitoring and counseling patients are crucial when starting new medications or adjusting doses.