transplant

10 interactions related to transplant

tacrolimus + grapefruit

Grapefruit furanocoumarins irreversibly inhibit intestinal CYP3A4, increasing tacrolimus AUC by roughly 28% and Cmax by up to 73%. Case reports describe trough levels tripling after grapefruit ingestion, producing nephrotoxicity and neurotoxicity.

high
tacrolimusgrapefruitcyp3a4furanocoumarinstransplantnephrotoxicityfood drug interactionimmunosuppressant

pomelo + tacrolimus

Pomelo contains furanocoumarins that inhibit intestinal CYP3A4 and P-glycoprotein, the two systems that limit tacrolimus absorption. A documented case in a renal transplant patient showed pomelo consumption nearly doubled tacrolimus blood levels, risking nephrotoxicity and neurotoxicity given tacrolimus's narrow therapeutic window.

critical
pomelotacrolimustransplantcyp3a4p-glycoproteinfuranocoumarinimmunosuppressantnephrotoxicitycase report

seville orange + cyclosporine

Seville orange juice contains furanocoumarins that reduce enterocyte CYP3A4 expression by approximately 40%, although a controlled human study found no significant change in cyclosporine AUC, likely because cyclosporine disposition also depends on intestinal P-glycoprotein, which Seville orange does not inhibit as strongly as grapefruit.

moderate
seville orangebitter orangecyclosporinetransplantcyp3a4p-glycoproteinfuranocoumarinimmunosuppressant

cranberry + tacrolimus

Cranberry juice has been shown to inhibit intestinal CYP3A enzymes, and tacrolimus is heavily metabolized by intestinal CYP3A4 and CYP3A5. The expected direction is an increase in tacrolimus trough levels, raising the risk of nephrotoxicity and tremor, although published cases are scarce and one case unexpectedly reported a decrease.

moderate
cranberrytacrolimustransplantcyp3a4immunosuppressantprografdrug interactionnephrotoxicity

cbd + tacrolimus

CBD inhibits CYP3A4, CYP3A5, and P-glycoprotein, the main pathways that clear tacrolimus. A published case report documented an approximately 3-fold rise in dose-normalized tacrolimus levels after adding CBD, posing serious nephrotoxicity, neurotoxicity, and over-immunosuppression risk in transplant patients.

critical
cbdtacrolimustransplantcyp3a4p-glycoproteinimmunosuppressantcalcineurin inhibitordrug interactionnephrotoxicity

probiotics + immunosuppressants

Live probiotic bacteria can translocate across the gut wall and cause bacteremia, endocarditis, or sepsis in patients whose immune systems are pharmacologically suppressed (e.g., calcineurin inhibitors, mTOR inhibitors, corticosteroids, mycophenolate). Multiple case reports document Lactobacillus and Bifidobacterium bloodstream infections in solid-organ and stem-cell transplant recipients.

high
probioticsimmunosuppressantsbacteremiatransplantinfection riskcontraindicationlactobacillusimmunocompromised

lactobacillus + tacrolimus

Tacrolimus is a calcineurin-inhibitor immunosuppressant used after solid-organ transplant. Lactobacillus species have caused bacteremia, endocarditis, and liver abscess in transplant recipients on tacrolimus, including a published case of recurrent Lactobacillus rhamnosus bacteremia in a renal transplant patient.

high
lactobacillustacrolimusprograftransplantbacteremiacalcineurin inhibitorimmunosuppressionrenal transplant

cyclosporine + grapefruit

Grapefruit juice contains furanocoumarins that irreversibly inhibit intestinal CYP3A4, raising cyclosporine bioavailability by 35-60% and increasing the risk of nephrotoxicity, hypertension, and neurotoxicity. The effect can persist for 24 hours or longer after a single glass.

high
cyclosporinegrapefruitcyp3a4furanocoumarinstransplantnephrotoxicityfood drug interactionimmunosuppressant

cyclosporine + echinacea

Echinacea is marketed as an immune stimulant and has been shown in vitro and in some animal models to activate macrophages, NK cells, and pro-inflammatory cytokines. While direct pharmacokinetic effects on cyclosporine levels are not well documented in humans, the immunostimulant pharmacology directly opposes the goal of immunosuppression in transplant and autoimmune patients.

moderate
cyclosporineechinaceaimmunosuppressanttransplantherb drug interactionimmune stimulationrejection riskautoimmune

grapefruit + sirolimus

Sirolimus is a CYP3A4 and P-glycoprotein substrate with a narrow therapeutic window and high baseline interpatient variability. The FDA-approved Rapamune label states that grapefruit juice inhibits the CYP3A4-mediated metabolism of sirolimus and must not be taken with or used to dilute the drug, because unpredictable, large rises in blood levels can cause nephrotoxicity, infection, and graft injury.

critical
grapefruitsirolimusrapamunerapamycincyp3a4p-glycoproteinimmunosuppressanttransplant