Rapamycin Conservation (stretching your supply)

#41

Examples of CYP3A4 Inhibitors (Categorized by Strength)

Strong Inhibitors

These cause a ≥5-fold increase in the blood levels of substrate drugs.

  • Antiretrovirals: Ritonavir , cobicistat (another booster, found in Stribild, Genvoya).
  • Antifungals: Ketoconazole, itraconazole, voriconazole, posaconazole.
  • Antibiotics: Clarithromycin, telithromycin.
  • Protease Inhibitors (for HCV): Boceprevir, telaprevir.
  • Others: Nefazodone, conivaptan.

Moderate Inhibitors

These cause a 2 to <5-fold increase in substrate drug levels.

  • Antifungals: Fluconazole, isavuconazole.
  • Cardiovascular: Diltiazem, verapamil.
  • Antibiotics: Erythromycin.
  • Food: Grapefruit juice and Seville oranges (bergamottin is the inhibiting compound).
  • Others: Ciprofloxacin, cimetidine, cyclosporine, imatinib.

Weak Inhibitors

These cause a 1.25 to 2-fold increase in substrate drug levels.

  • Many common drugs fall here, including amlodipine, ranolazine, and others. While “weak,” they can still be significant when combined with a narrow therapeutic index drug.

From the strong inhibitor list, I am going to have trouble getting a script from a local doctor…

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#42

The inhibition of CYP3A4 from GFJ can last up to 1-3 days even though from my self administration 2-3 hours after is the best. As for Ritonavir it is stated that it could last up to 5-7 days…

#43

No side effects from Ritonavir as far as I can discern (from that one dose a day before rapa). Recall that it is not uncommon to use Ritonavir as a booster with various medications, such as in Paxlovid against SARS-CoV-2, i.e., quite a common medication. And yes, because Ritonavir irreversibly inhibits CYP3A, its effect on raising Rapa levels may be prolonged, another reason to consider longer dosing intervals.

#44

i think I’ll go back to 2 weeks interval. easier to manage.