St. PETERsburg Pain and Alcohol Intervention With Naltrexone and Gabapentin

4.5 mg of low dose naltrexone taken once daily for 8 weeks. In week 1, participants will take 4.5mg of naltrexone once daily. In week 2, participants will take 4.5mg of naltrexone once daily, and a placebo capsule twice daily. In weeks 3 through 7, participants will take 1 placebo capsule with 4.5 mg mg of naltrexone once daily, and 2 placebo capsules twice daily. In week 8, in days 1-4 participants will take 4.5 mg of naltrexone with a placebo capsule once daily and 2 placebo capsules twice daily; in days 5-7, participants will take 4.5 mg of naltrexone once daily, and a placebo capsule twice daily.

Dose will begin at 300 mg daily (300 mg qd), in week 2 the dose will be titrated up to 900 mg daily (300 mg tid). In week 3, the dose will be titrated to 1800 mg daily ( 2 capsules of 300 mg tid) and participants will remain on that dose until week 8. In week 8, in days 1-4 participants will take 1800 mg daily (300 mg+300 mg tid); in days 5-7, participants will take 900 mg daily (300 mg of gabapentin three times daily).

In week 1, participants will take 1 placebo capsule once daily. In week 2, participants will take 1 placebo capsule three times per day. In weeks 3 through 7, 2 placebo capsules three times per day. In week 8, in days 1-4 participants will take 2 placebo capsules three times per day; in days 5-7, participants will take 1 placebo capsule three times per day. The placebo medications will be composed of lactose and will not contain active ingredients.