The goal of this clinical trial is to learn about the use of turmeric (Curcumin) as a treatment for pain of thumb-joint arthritis. Turmeric is commonly being used as an over-the-counter treatment for musculoskeletal pain. Clinical trials have demonstrated a pain-relief benefit for knee osteoarthritis, however no clinical trial has been performed to establish efficacy of curcumin in humans for thumb-joint arthritis. The main question[s] it aims to answer are:

• Is Turmeric more effective than placebo at relieving pain for thumb-joint arthritis? A placebo is a look-alike substance that contains no active drug.
• Is Turmeric more effective than placebo at improving patient-reported outcomes for CMC arthritis?
• Is Turmeric safe for participants with thumb-joint arthritis?

Participants will:

• take 4 weeks of daily Turmeric capsules,
• take 4 weeks of daily placebo capsules
• answer daily surveys about how they are feeling and functioning.

This randomized controlled trial of oral curcumin for the treatment of pain of CMC arthritis will investigate the therapeutic potential of curcumin as an oral treatment for pain of CMC arthritis. Rationale: Curcumin is commonly being used as an over-the-counter treatment for musculoskeletal pain. Clinical trials have demonstrated a pain-relief benefit for knee osteoarthritis, however no clinical trial has been performed to establish efficacy of curcumin in humans for CMC arthritis. Hypothesis: Curcumin is more effective than placebo for relieving pain and improving patient-reported outcomes for CMC arthritis Study Design: The study design will be a double-blind, randomized controlled trial with crossover. Treatment will be blinded to the subjects and investigators. Patients will be randomly assigned 4 weeks of the Curcumin or control and then crossover to the other condition for 4 additional weeks. Patients will take the oral curcumin or control placebo capsule twice daily. Subjects will be advised to observe adverse effects.

The study design will be a double-blind randomized control trial with crossover. Treatment will be blinded to the subjects and investigators. Patients will be randomly assigned 4 weeks of the case (curcumin) or control capsules and then crossover to the other condition for 4 more weeks with a 2-week washout interval between. Patients will take one oral capsule by mouth twice daily. The subjects will be advised to observe for physiologic changes, skin changes, or other adverse effects. If mild to severe adverse events are noticed, the patient's will discontinue the use of the capsules, and appropriate care and observation will be taken. Each condition will last for 4 weeks and then subjects will be contacted by the study coordinator to facilitate crossover into the other condition following a 2-week washout period. To capture any delayed-onset adverse events, subjects will attend a follow-up visit seven days following the last dose of the curcumin capsule.

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)

Double-blind Randomized Controlled Trial