Drug-Drug Interaction Between Orally Administered Hydrocodone-Acetaminophen and Inhalation of Cannabis Smoke: A Case Report

Objective: To determine if a 2-day protocol measuring pharmacokinetic and pharmacodynamic characteristics can demonstrate drug-drug interactions when smoked cannabis is added to orally administered hydrocodone/acetaminophen combination products. Case Summary: A 51-year-old non-Hispanic white male with chronic pain diagnoses participated in a 2-day pilot protocol. The participant attended two 7-hour in-lab days where he received 10 blood draws each day and completed self-administered pain and anxiety surveys. For both days, the participant took his prescribed dose of hydrocodone/acetaminophen (1/2 tablet of 7.5 mg/325 mg combination product) with the addition of 1 smoked pre-rolled marijuana cigarette (labeled as 0.5 g; 22.17% Δ9-tetrahydrocannabinol; 0.12% cannabidiol) on Day 2. Blood specimens were analyzed using mass spectrometry to quantify the difference of plasma hydrocodone levels between Day 1 and Day 2. Results: Compared to Day 1, lower levels of pain and anxiety were reported during Day 2 with the addition of cannabis to oral hydrocodone/acetaminophen. Day 2 pharmacokinetic analysis also revealed more rapid absorption and overall lower levels of hydrocodone in plasma. Discussion: Lower hydrocodone plasma levels in Day 2 may indicate cannabis’s effect on metabolism and reduce the risk of opioid toxicity. The quicker absorption rate of hydrocodone could explain lower pain and anxiety scores reported on the second day. Conclusion and Relevance: A 2-day protocol was able to capture differences across time in pharmacokinetic and pharmacodynamic measurements. Larger studies can be designed to better characterize the potential drug-drug interaction of cannabis and opioids.

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Pseudo-Parkinson Disease Secondary to Ritonavir–Buspirone Interaction

Annals of Pharmacotherapy ◽

10.1177/106002800303700207 ◽

2003 ◽

Vol 37 (2) ◽

pp. 202-205 ◽

Cited By ~ 9

Author(s):

Patrick G Clay ◽

Molly M Adams

Keyword(s):

Drug Interaction ◽

Inhibitory Effect ◽

Hiv Positive ◽

High Dose ◽

Resting Tremor ◽

Case Summary ◽

History Of ◽

Drug Drug Interaction ◽

To Receive

OBJECTIVE: To report a case of Parkinson-like symptoms appearing in a patient after introduction of ritonavir to buspirone therapy. CASE SUMMARY: A 54-year-old HIV-positive white man presented to the clinic with a 2-week history of ataxia, shuffling gait, cogwheel rigidity, resting tremor, and sad affect with masked features. This patient had been receiving high-dose buspirone (40 mg every morning and 30 mg every evening) for 2 years prior to the introduction of ritonavir/indinavir combination therapy (400 mg/400 mg twice daily) 6 weeks prior to initiation of the above symptoms. Buspirone was decreased to 15 mg 3 times daily, ritonavir/indinavir was discontinued, and amprenavir 1200 mg twice daily was added. The patient's symptoms began to subside after 1 week, with complete resolution after about 2 weeks. The patient continued to receive buspirone for an additional 12 months without recurrence of symptoms. DISCUSSION: This is the first reported interaction of buspirone and antiretrovirals. Buspirone, extensively metabolized by CYP3A4, was likely at supratherapeutic levels due to the inhibitory effect of ritonavir and, secondarily, indinavir. The Parkinson-like symptoms developed rapidly and severely, impacted this patient's quality of life, and necessitated significant clinic expenditures to identify this drug–drug interaction. CONCLUSIONS: This case demonstrates a severe drug–drug interaction between buspirone and ritonavir and further demonstrates the need for awareness of the metabolic profile for all agents an HIV-infected patient is receiving.

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A phase 1, open-label, drug–drug interaction study of rucaparib with rosuvastatin and oral contraceptives in patients with advanced solid tumors

Cancer Chemotherapy and Pharmacology ◽

10.1007/s00280-021-04338-7 ◽

2021 ◽

Author(s):

Mingxiang Liao ◽

Krzysztof G. Jeziorski ◽

Monika Tomaszewska-Kiecana ◽

István Láng ◽

Marek Jasiówka ◽

...

Keyword(s):

Drug Interaction ◽

Solid Tumors ◽

Oral Contraceptives ◽

Interaction Analysis ◽

Phase 1 ◽

Geometric Mean ◽

Pharmacokinetic Analysis ◽

Advanced Solid Tumors ◽

Open Label ◽

Drug Drug Interaction

Abstract Purpose This study aimed at evaluating the effect of rucaparib on the pharmacokinetics of rosuvastatin and oral contraceptives in patients with advanced solid tumors and the safety of rucaparib with and without coadministration of rosuvastatin or oral contraceptives. Methods Patients received single doses of oral rosuvastatin 20 mg (Arm A) or oral contraceptives ethinylestradiol 30 µg + levonorgestrel 150 µg (Arm B) on days 1 and 19 and continuous doses of rucaparib 600 mg BID from day 5 to 23. Serial blood samples were collected with and without rucaparib for pharmacokinetic analysis. Results Thirty-six patients (n = 18 each arm) were enrolled and received at least 1 dose of study drug. In the drug–drug interaction analysis (n = 15 each arm), the geometric mean ratio (GMR) of maximum concentration (Cmax) with and without rucaparib was 1.29 for rosuvastatin, 1.09 for ethinylestradiol, and 1.19 for levonorgestrel. GMR of area under the concentration–time curve from time zero to last quantifiable measurement (AUC0–last) was 1.34 for rosuvastatin, 1.43 for ethinylestradiol, and 1.56 for levonorgestrel. There was no increase in frequency of treatment-emergent adverse events (TEAEs) when rucaparib was given with either of the probe drugs. In both arms, most TEAEs were mild in severity and considered unrelated to study treatment. Conclusion Rucaparib 600 mg BID weakly increased the plasma exposure to rosuvastatin or oral contraceptives. Rucaparib safety profile when coadministered with rosuvastatin or oral contraceptives was consistent with that of rucaparib monotherapy. Dose adjustments of rosuvastatin and oral contraceptives are not necessary when coadministered with rucaparib. ClinicalTrials.gov NCT03954366; Date of registration May 17, 2019.

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