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Drug Interactions between letrozole / ribociclib and Septra DS

This report displays the potential drug interactions for the following 2 drugs:

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Interactions between your drugs

Moderate

letrozole ribociclib

Applies to: letrozole / ribociclib and letrozole / ribociclib

MONITOR: Coadministration with ribociclib may increase the plasma concentrations and pharmacologic effects of drugs that are substrates of CYP450 3A4. The proposed mechanism is decreased clearance due to ribociclib-mediated inhibition of CYP450 3A4 metabolism. In healthy study subjects, administration of midazolam, a sensitive CYP450 3A4 substrate, with multiple 400 mg daily doses of ribociclib increased the midazolam peak plasma concentration (Cmax) and systemic exposure (AUC) by 2.1-fold and 3.8-fold, respectively, compared to midazolam administered alone. When given at a clinically relevant dose of 600 mg daily, ribociclib is predicted to increase midazolam Cmax and AUC by 2.4-fold and 5.2-fold, respectively.

MANAGEMENT: Caution is advised when ribociclib is used concomitantly with drugs that undergo metabolism by CYP450 3A4, particularly those with a narrow therapeutic range. Dosage adjustments as well as clinical and laboratory monitoring may be appropriate for some drugs whenever ribociclib is added to or withdrawn from therapy.

References

  1. Zhou XJ, Zhou-Pan XR, Gauthier T, Placidi M, Maurel P, Rahmani R (1993) "Human liver microsomal cytochrome P450 3A isozymes mediated vindesine biotransformation. Metabolic drug interactions." Biochem Pharmacol, 45, p. 853-61
  2. Trivier JM, Libersa C, Belloc C, Lhermitte M (1993) "Amiodarone N-deethylation in human liver microsomes: involvement of cytochrome P450 3A enzymes (first report)." Life Sci, 52, pl91-6
  3. Rawden HC, Kokwaro GO, Ward SA, Edwards G (2000) "Relative contribution of cytochromes P-450 and flavin-containing monoxygenases to the metabolism of albendazole by human liver microsomes." Br J Clin Pharmacol, 49, p. 313-22
  4. DSouza DL, Levasseur LM, Nezamis J, Robbins DK, Simms L, Koch KM (2001) "Effect of alosetron on the pharmacokinetics of alprazolam." J Clin Pharmacol, 41, p. 452-4
  5. Katoh M, Nakajima M, Yamazaki H, Yokoi T (2001) "Inhibitory effects of CYP3A4 substrates and their metabolites on P-glycoprotein-mediated transport." Eur J Pharm Sci, 12, p. 505-13
  6. Kane GC, Lipsky JJ (2000) "Drug-grapefruit juice interactions." Mayo Clin Proc, 75, p. 933-42
  7. Yu DK (1999) "The contribution of P-glycoprotein to pharmacokinetic drug-drug interactions." J Clin Pharmacol, 39, p. 1203-11
  8. Nagy J, Schipper HG, Koopmans RP, Butter JJ, van Boxtel CJ, Kager PA (2002) "Effect of grapefruit juice or cimetidine coadministration on albendazole bioavailability." Am J Trop Med Hyg, 66, p. 260-3
  9. (2017) "Product Information. Kisqali (ribociclib)." Novartis Pharmaceuticals
View all 9 references

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Minor

sulfamethoxazole ribociclib

Applies to: Septra DS (sulfamethoxazole / trimethoprim) and letrozole / ribociclib

Limited data suggest that sulfamethoxazole-trimethoprim (SMX-TMP) may rarely prolong the QT interval of the electrocardiogram. Theoretically, coadministration with other agents that can prolong the QT interval may result in additive effects and increased risk of ventricular arrhythmias including torsade de pointes and sudden death. There have been isolated reports of QT prolongation and ventricular arrhythmias occurring in patients treated with SMX-TMP intravenously. However, a causal relationship has not been established, and the risk of clinically significant QT prolongation is unlikely at recommended dosages of SMX-TMP. In general, the risk of an individual agent or a combination of agents causing ventricular arrhythmia in association with QT prolongation is largely unpredictable but may be increased by certain underlying risk factors such as congenital long QT syndrome, cardiac disease, and electrolyte disturbances (e.g., hypokalemia, hypomagnesemia). In addition, the extent of drug-induced QT prolongation is dependent on the particular drug(s) involved and dosage(s) of the drug(s). Patients should be advised to seek prompt medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, lightheadedness, fainting, palpitation, irregular heart rhythm, shortness of breath, or syncope.

References

  1. Wiener I, Rubin D, Martinez E, et al. (1981) "QT prolongation and paroxysmal ventricular tachycardia occurring during fever following trimethoprim-sulfamethoxazole administration." Mt Sinai J Med, 48, p. 53-5
  2. Crouch MA, Limon L, Cassano AT (2003) "Clinical relevance and management of drug-related QT interval prolongation." Pharmacotherapy, 23, p. 881-908
  3. Lopez JA, Harold JG, Rosenthal MC, Oseran DS, Schapira JN, Peter T (1987) "QT prolongation and torsades de pointes after administration of trimethoprin-sulfamethoxazole." Am J Cardiol, 59, p. 376-7
  4. Cerner Multum, Inc. "UK Summary of Product Characteristics."
  5. Canadian Pharmacists Association (2006) e-CPS. http://www.pharmacists.ca/function/Subscriptions/ecps.cfm?link=eCPS_quikLink
  6. Cerner Multum, Inc. "Australian Product Information."
  7. Darpo B (2001) "Spectrum of drugs prolonging QT interval and the incidence of torsades de pointes." Eur Heart J Suppl, 3(Suppl K), K70-80
View all 7 references

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Drug and food interactions

Moderate

ribociclib food

Applies to: letrozole / ribociclib

GENERALLY AVOID: Pomegranates and grapefruit may increase the systemic exposure to ribociclib. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in these fruits. Increased exposure to ribociclib may increase the risk of adverse effects such as infections, neutropenia, leukopenia, anemia, thrombocytopenia, anorexia, nausea, vomiting, diarrhea, stomatitis, alopecia, fatigue, headache, and abnormal liver function may be increased.

MANAGEMENT: Patients receiving ribociclib should avoid consumption of pomegranates or pomegranate juice and grapefruit or grapefruit juice during treatment.

References

  1. (2017) "Product Information. Kisqali (ribociclib)." Novartis Pharmaceuticals

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Moderate

sulfamethoxazole food

Applies to: Septra DS (sulfamethoxazole / trimethoprim)

MONITOR: Two cases have been reported in which patients on sulfamethoxazole-trimethoprim therapy, after consuming beer, reported flushing, heart palpitations, dyspnea, headache, and nausea (disulfiram - alcohol type reactions). First-generation sulfonylureas have been reported to cause facial flushing when administered with alcohol by inhibiting acetaldehyde dehydrogenase and subsequently causing acetaldehyde accumulation. Since sulfamethoxazole is chemically related to first-generation sulfonylureas, a disulfiram-like reaction with products containing sulfamethoxazole is theoretically possible. However, pharmacokinetic/pharmacodynamic data are lacking and in addition, the two reported cases cannot be clearly attributed to the concomitant use of sulfamethoxazole-trimethoprim and alcohol.

MANAGEMENT: Patients should be alerted to the potential for this interaction and although the risk for this interaction is minimal, caution is recommended while taking sulfamethoxazole-trimethoprim concomitantly with alcohol.

References

  1. Heelon MW, White M (1998) "Disulfiram-cotrimoxazole reaction." Pharmacotherapy, 18, p. 869-70
  2. Mergenhagen KA, Wattengel BA, Skelly MK, Clark CM, Russo TA (2020) "Fact versus fiction: a review of the evidence behind alcohol and antibiotic interactions." Antimicrob Agents Chemother, 64, e02167-19

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Therapeutic duplication warnings

No warnings were found for your selected drugs.

Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.


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Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No interaction information available.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.