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Drug Interactions between letrozole / ribociclib and Protostat

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

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Interactions between your drugs

Moderate

metroNIDAZOLE ribociclib

Applies to: Protostat (metronidazole) and letrozole / ribociclib

MONITOR: QT prolongation has been reported with metronidazole, particularly when administered with drugs that have the potential for prolonging the QT interval. This may increase the risk of ventricular arrhythmias associated with QT prolongation including torsade de pointes and sudden death. According to the manufacturer, flattening of the T-wave has been observed in electrocardiographic tracings. 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).

MANAGEMENT: Caution is recommended when metronidazole is used concomitantly with agents known to cause QT prolongation. 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. (2001) "Product Information. Flagyl (metronidazole)." Searle
  2. Kounas SP, Letsas KP, Sideris A, Efraimidis M, Kardaras F (2005) "QT interval prolongation and torsades de pointes due to a coadministration of metronidazole and amiodarone." Pacing Clin Electrophysiol, 28, p. 472-3
  3. Cerner Multum, Inc. "Australian Product Information."
  4. (2022) "Product Information. Pylera (bismuth subcitrate potassium/metronidazo/TCN)." Aptalis Pharma
View all 4 references

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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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Drug and food interactions

Major

metroNIDAZOLE food

Applies to: Protostat (metronidazole)

CONTRAINDICATED: Use of alcohol or products containing alcohol during nitroimidazole therapy may result in a disulfiram-like reaction in some patients. There have been a few case reports involving metronidazole, although data overall are not convincing. The presumed mechanism is inhibition of aldehyde dehydrogenase (ALDH) by metronidazole in a manner similar to disulfiram. Following ingestion of alcohol, inhibition of ALDH results in increased concentrations of acetaldehyde, the accumulation of which can produce an unpleasant physiologic response referred to as the 'disulfiram reaction'. Symptoms include flushing, throbbing in head and neck, throbbing headache, respiratory difficulty, nausea, vomiting, sweating, thirst, chest pain, palpitation, dyspnea, hyperventilation, tachycardia, hypotension, syncope, weakness, vertigo, blurred vision, and confusion. Severe reactions may result in respiratory depression, cardiovascular collapse, arrhythmia, myocardial infarction, acute congestive heart failure, unconsciousness, convulsions, and death. However, some investigators have questioned the disulfiram-like properties of metronidazole. One study found neither elevations in blood acetaldehyde nor objective or subjective signs of a disulfiram-like reaction to ethanol in six subjects treated with metronidazole (200 mg three times a day for 5 days) compared to six subjects who received placebo.

MANAGEMENT: Because clear evidence is lacking concerning the safety of ethanol use during nitroimidazole therapy, patients should be apprised of the potential for interaction. Consumption of alcoholic beverages and products containing propylene glycol is specifically contraindicated during and for at least 3 days after completion of metronidazole and benznidazole therapy according to their product labeling.

References

  1. Giannini AJ, DeFrance DT (1983) "Metronidazole and alcohol: potential for combinative abuse." J Toxicol Clin Toxicol, 20, p. 509-15
  2. Alexander I (1985) "Alcohol-antabuse syndrome in patients receiving metronidazole during gynaecological treatment." Br J Clin Pract, 39, p. 292-3
  3. Harries DP, Teale KF, Sunderland G (1990) "Metronidazole and alcohol: potential problems." Scott Med J, 35, p. 179-80
  4. (2001) "Product Information. Flagyl (metronidazole)." Searle
  5. Edwards DL, Fink PC, Van Dyke PO (1986) "Disulfiram-like reaction associated with intravenous trimethoprim-sulfamethoxazole and metronidazole." Clin Pharm, 5, p. 999-1000
  6. Williams CS, Woodcock KR (2000) "Do ethanol and metronidazole interact to produce a disulfiram-like reaction?." Ann Pharmacother, 34, p. 255-7
  7. Visapaa JP, Tillonen JS, Kaihovaara PS, Salaspuro MP (2002) "Lack of disulfiram-like reaction with metronidazole and ethanol." Ann Pharmacother, 36, p. 971-4
  8. Krulewitch CJ (2003) "An unexpected adverse drug effect." J Midwifery Womens Health, 48, p. 67-8
  9. (2017) "Product Information. Benznidazole (benznidazole)." Everett Laboratories Inc
View all 9 references

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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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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.