The short answer
Grapefruit juice can increase exposure to oral diazepam and may prolong its effects. The human study did not establish a sedation rate or a safe timing gap, and its result cannot be assigned to every grapefruit extract or nonoral formulation.
What this answer covers
Citrus paradisi; direct evidence is juice, not seed extract or every fruit-extract product.
- Supplement or preparation
- Citrus paradisi
- Medication ingredient
- diazepam
A small human study found higher exposure
Healthy volunteers taking oral diazepam with grapefruit juice had higher measured exposure and a later peak than with water. The study measured drug concentrations rather than establishing how often excessive sedation occurred.
Metabolism and active metabolites matter
Diazepam is converted by CYP3A4 and CYP2C19 to active metabolites. Parent-drug exposure alone does not fully describe the duration or intensity of all effects, especially with repeated dosing.
Keep the route and preparation separate
Juice is not interchangeable with grapefruit seed extract or every concentrated fruit product. Injected and nasal diazepam have different absorption pathways, so the oral study’s numerical increase is not their measured interaction.
Review grapefruit use with the prescriber
Ask before changing regular grapefruit use, and do not adjust diazepam or rely on a short interval yourself. Follow the prescribed seizure-rescue plan when relevant. Marked sedation, breathing difficulty or inability to wake needs urgent help.
Evidence and practical considerations
Timing & monitoring
Direct oral-juice PK increase supports conditional exposure/sedation and co-use review; no clinical sedation incidence, universal botanical equivalence or protective spacing demonstrated.
- Exact scope
- Citrus paradisi; direct evidence is juice, not seed extract or every fruit-extract product. with Diazepam3322 IN; oral, IV/IM and intranasal formulations, active metabolites and study-route limits.
- Medication form and route
- oral medication; intravenous medication; intramuscular medication; intranasal medication; oral supplement
What remains uncertain
- No unmeasured pair incidence, blanket class transfer or arbitrary spacing interval.
Factors that may matter: Preparation; Dose; Other medicines; Organ function.
Read the supporting source summaries
Source 1: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People prescribed diazepam
CNS-depressant risk; CYP3A4/2C19 formation of active metabolites with prolonged elimination.
How this applies: Exact diazepam RxCUI 3322 IN, with stated salt/formulation/route bridge.
Not midazolam metabolism or proof of exact botanical risk.
Source 2: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People prescribed diazepam
Sedation and respiratory precautions with other CNS depressants.
How this applies: Exact diazepam RxCUI 3322 IN, with stated salt/formulation/route bridge.
Bypasses intestinal absorption; oral juice exposure magnitude cannot be transferred.
Source 3: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People prescribed diazepam
CNS-depressant and metabolism-related interaction precautions; exact rescue dosing directions.
How this applies: Exact diazepam RxCUI 3322 IN, with stated salt/formulation/route bridge.
Not oral-study dosing or a basis to delay prescribed rescue treatment; rectal preparations not directly studied here.
Source 4: original human study
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: Eight healthy male/female volunteers.
Diazepam AUC over24hours increased3.2-fold and peak concentration1.5-fold; time to peak delayed.
How this applies: Eight-person study,24hour sampling and whole-blood enzyme immunoassay; no demonstrated clinical sedation rate or equivalence to every extract.
Eight-person study,24hour sampling and whole-blood enzyme immunoassay; no demonstrated clinical sedation rate or equivalence to every extract.
Research assessment: · Open full citations ↗
Absorption & effectiveness
Direct oral-juice PK increase supports conditional exposure/sedation and co-use review; no clinical sedation incidence, universal botanical equivalence or protective spacing demonstrated.
- Exact scope
- Citrus paradisi; direct evidence is juice, not seed extract or every fruit-extract product. with Diazepam3322 IN; oral, IV/IM and intranasal formulations, active metabolites and study-route limits.
- Medication form and route
- oral medication; intravenous medication; intramuscular medication; intranasal medication; oral supplement
What remains uncertain
- No unmeasured pair incidence, blanket class transfer or arbitrary spacing interval.
Factors that may matter: Preparation; Dose; Other medicines; Organ function.
Read the supporting source summaries
Source 1: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People prescribed diazepam
CNS-depressant risk; CYP3A4/2C19 formation of active metabolites with prolonged elimination.
How this applies: Exact diazepam RxCUI 3322 IN, with stated salt/formulation/route bridge.
Not midazolam metabolism or proof of exact botanical risk.
Source 2: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People prescribed diazepam
Sedation and respiratory precautions with other CNS depressants.
How this applies: Exact diazepam RxCUI 3322 IN, with stated salt/formulation/route bridge.
Bypasses intestinal absorption; oral juice exposure magnitude cannot be transferred.
Source 3: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People prescribed diazepam
CNS-depressant and metabolism-related interaction precautions; exact rescue dosing directions.
How this applies: Exact diazepam RxCUI 3322 IN, with stated salt/formulation/route bridge.
Not oral-study dosing or a basis to delay prescribed rescue treatment; rectal preparations not directly studied here.
Source 4: original human study
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: Eight healthy male/female volunteers.
Diazepam AUC over24hours increased3.2-fold and peak concentration1.5-fold; time to peak delayed.
How this applies: Eight-person study,24hour sampling and whole-blood enzyme immunoassay; no demonstrated clinical sedation rate or equivalence to every extract.
Eight-person study,24hour sampling and whole-blood enzyme immunoassay; no demonstrated clinical sedation rate or equivalence to every extract.
Research assessment: · Open full citations ↗
Side effects & toxicity
Direct oral-juice PK increase supports conditional exposure/sedation and co-use review; no clinical sedation incidence, universal botanical equivalence or protective spacing demonstrated.
- Exact scope
- Citrus paradisi; direct evidence is juice, not seed extract or every fruit-extract product. with Diazepam3322 IN; oral, IV/IM and intranasal formulations, active metabolites and study-route limits.
- Medication form and route
- oral medication; intravenous medication; intramuscular medication; intranasal medication; oral supplement
What remains uncertain
- No unmeasured pair incidence, blanket class transfer or arbitrary spacing interval.
Factors that may matter: Preparation; Dose; Other medicines; Organ function.
Read the supporting source summaries
Source 1: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People prescribed diazepam
CNS-depressant risk; CYP3A4/2C19 formation of active metabolites with prolonged elimination.
How this applies: Exact diazepam RxCUI 3322 IN, with stated salt/formulation/route bridge.
Not midazolam metabolism or proof of exact botanical risk.
Source 2: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People prescribed diazepam
Sedation and respiratory precautions with other CNS depressants.
How this applies: Exact diazepam RxCUI 3322 IN, with stated salt/formulation/route bridge.
Bypasses intestinal absorption; oral juice exposure magnitude cannot be transferred.
Source 3: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People prescribed diazepam
CNS-depressant and metabolism-related interaction precautions; exact rescue dosing directions.
How this applies: Exact diazepam RxCUI 3322 IN, with stated salt/formulation/route bridge.
Not oral-study dosing or a basis to delay prescribed rescue treatment; rectal preparations not directly studied here.
Source 4: original human study
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: Eight healthy male/female volunteers.
Diazepam AUC over24hours increased3.2-fold and peak concentration1.5-fold; time to peak delayed.
How this applies: Eight-person study,24hour sampling and whole-blood enzyme immunoassay; no demonstrated clinical sedation rate or equivalence to every extract.
Eight-person study,24hour sampling and whole-blood enzyme immunoassay; no demonstrated clinical sedation rate or equivalence to every extract.
Research assessment: · Open full citations ↗
Review and change history
- Publication status
- Published research summary
- Clinical review
- Not yet recorded
| Date | Update |
|---|---|
| Research summary published | |
| Article prepared | |
| Prepared exact diazepam article with formulation-specific evidence and uncertainty. |
Article revision: 5c4a31dd074b682c
This guide brings together the evidence records used by our interaction checker. Each finding retains its own preparation limits, research date, and source summaries.
Full citations require verification. Reading this answer and the source summaries does not.
Taking other supplements or medications?
Use the checker to explore your other combinations. Ask a pharmacist to review the exact products, amounts and medical conditions in your complete list.
Open the interaction checkerInformation, not medical advice. Do not change prescribed treatment based on this guide.