Turmeric vs. placebo: will this spice soothe your aching thumb?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: 1. Provision of signed and dated informed consent form. 2. Stated willingness to comply with all study procedures and availability for the duration of the study. 3. Male or female, aged 18 years or older. 4. For females, must be willing to use an approved form of birth control during this study. Acceptable forms of birth control: * Norplant * IUD (intrauterine device) * Birth Control Patch * Depo-Provera * Sterilization The following may be used if combined with other birth control methods: * Condoms * Diaphragm * Jellies or foam * Cervical cap * Sponge 5. For males, must be willing to not father a baby for the duration of the study and for 90 days after the last dose of study drug, or donate to a sperm back during this time. Must be willing to use an approved form of birth control during this time. Acceptable forms of birth control: * Condoms * Sterilization 6. Daily visual analog pain greater than 5 and ≤ 9 out of 10. 7. Duration of pain for greater than 30 days. 8. Presence of radiographically confirmed diagnosis of thumb basal joint arthritis Exclusion Criteria: 1. Participant does not speak English. 2. Participant is blind. 3. Severe cardiac, pulmonary, liver, gastrointestinal and hematological disease (including coagulopathy), and /or renal disease. 4. Abnormal hematological, coagulation, and/or liver function test results. 5. Coumadin use at time of screening. 6. Use of any anticoagulant and antiplatelet medication. 7. History of mental illness. 8. Participant who is incarcerated. 9. History of drug or substance abuse. 10. Pre-existing curcumin or turmeric product usage within 3 months of the study period. 11. Participant has had a corticosteroid injection ≤ 60 days prior. 12. Participant has had prior surgery for osteoarthritis treatment 13. Participant who has fibromyalgia and post-operative pain. 14. Females who are pregnant, nursing or planning a pregnancy 15. Participants within 14 days of the study procedure taking prescription or non-prescription medication which are substrates of CYP3A4: * Itraconazole, * Ketoconazole, * Azamulin, * Troleandomycin, * Verapamil, * John's wart, * Phenobarbital, 16. Participants within 14 days of the study procedure taking prescription or non-prescription medication which are substrates of CYP2C19: * Nootkatone, * Ticlopidine, * Rifampin, * Omeprazole), 17. Participants within 14 days of the study procedure taking prescription or non-prescription medication which are substrates of CYP2C8: * Montelukast, * Quercetin, * Phenelzine, * Rifampin, * Clopidogrel , 18. Participants within 14 days of the study procedure taking prescription or non-prescription medication which are substrates of CYP2C9: * Sulfaphenazole, * Tienilic acid, * Carbamazepine, * Apoflutamide , * Fluconazole, * Celecoxib, 19. Participants within 14 days of the study procedure taking prescription or non-prescription medication which are substrates of CYP1A2: * alpha-Naphthoflavone, * Furafylline, * Phenytoin, * Rifampin, * Ritonavir, * smoking, * Teriflunomide, * Ciprofloxacin, * oral contraceptives, * Allopurinol 20. Participants within 14 days of the study procedure taking prescription or non-prescription medication which are substrates of CYP2B6 : * Sertraline, * Phencyclidine, * Thiotepa, * Ticlopidine, * Carbamazepine, * Efavirenz, * Rifampin, * Bupropion)