Gabapentin (Gabarone, Gralise, Horizant) — 2026 Medicare Part D coverage
gabapentin — sold as Gabarone, Gralise, Horizant, Neurontin, Relgaabi: 29 forms appear in Medicare Part D formularies for 2026. This page reports what plans filed with CMS; it does not recommend a plan.
Which plans in your county cover gabapentin?
Pick a county to see every Medicare Advantage plan filed there and every stand-alone Part D plan in its region, with this drug's tier, restrictions and tier cost sharing.
How to read drug coverage
Tier is the cost-sharing tier the plan assigned the drug in its CMS formulary filing; lower tiers usually cost less. PA = prior authorization, ST = step therapy (try another drug first), QL = quantity limit. Not on formulary means the plan did not list this exact form; the plan may cover another strength or a formulary exception may be possible. Cost sharing is the plan's initial-coverage amount for the tier as filed with CMS; the deductible, the $2,100 annual out-of-pocket cap, the $35 insulin cap and negotiated prices for selected drugs can change what you actually pay. Formularies change during the year; the plan's formulary document and Medicare.gov govern.
What the star rating under each Medicare Advantage plan means
What the star rating means. CMS rates every Medicare Advantage contract (the "H" number in the plan ID — all plans under it share the rating) on a 1-to-5 scale each October, from about 40 measures of care quality, member experience, complaints and appeals, customer service and, for plans with drug coverage, drug safety and pricing. The 2026 rating is largely based on performance measured in 2024.
5 Excellent4 Above average3 Average2 Below average1 Poor
Not rated means CMS published no overall rating — usually a contract too new to be measured or with too few members ("not enough data"); it is not a low score. A 5-star contract can be joined outside the normal enrollment windows (the 5-star Special Enrollment Period, Dec 8 – Nov 30). Medicare.gov flags contracts rated below 3 stars for three years running as low-performing. Stars describe the contract's past performance as CMS measured it; they are not a recommendation, and they do not tell you whether a plan's network, drugs or costs fit you.
Forms and strengths in 2026 formularies
| Form | Formularies listing it | Most common tier | PA | ST | QL |
|---|---|---|---|---|---|
| gabapentin 100 MG Oral Capsule generic · RxCUI 310430 | 328 (100%) | 2 | 0 | 0 | 290 |
| gabapentin 250 MG in 5 mL Oral Solution generic · RxCUI 283523 | 328 (100%) | 3 | 0 | 0 | 290 |
| gabapentin 300 MG Oral Capsule generic · RxCUI 310431 | 328 (100%) | 2 | 0 | 0 | 290 |
| gabapentin 400 MG Oral Capsule generic · RxCUI 310432 | 328 (100%) | 2 | 0 | 0 | 288 |
| gabapentin 600 MG Oral Tablet generic · RxCUI 310433 | 328 (100%) | 2 | 0 | 0 | 290 |
| gabapentin 800 MG Oral Tablet generic · RxCUI 310434 | 328 (100%) | 2 | 0 | 0 | 288 |
| Relgaabi 300 MG Oral Capsule brand · RxCUI 2740839 | 95 (29%) | 2 | 0 | 11 | 90 |
| Relgaabi 400 MG Oral Capsule brand · RxCUI 2740841 | 95 (29%) | 2 | 0 | 11 | 90 |
| gabapentin 600 MG Once-Daily Oral Tablet generic · RxCUI 1806382 | 33 (10%) | 4 | 28 | 0 | 29 |
| gabapentin 300 MG Once-Daily Oral Tablet generic · RxCUI 1806380 | 32 (10%) | 4 | 28 | 0 | 31 |
| gabapentin 450 MG Once-Daily Oral Tablet generic · RxCUI 2634747 | 27 (8%) | 3 | 25 | 0 | 27 |
| gabapentin 750 MG Once-Daily Oral Tablet generic · RxCUI 2634751 | 27 (8%) | 3 | 25 | 0 | 27 |
| gabapentin 900 MG Once-Daily Oral Tablet generic · RxCUI 2634743 | 27 (8%) | 3 | 25 | 0 | 27 |
| Relgaabi 200 MG Oral Capsule brand · RxCUI 2739007 | 21 (6%) | 5 | 0 | 11 | 18 |
| Gabarone 100 MG Oral Tablet brand · RxCUI 602399 | 7 (2%) | 4 | 1 | 0 | 0 |
| Gabarone 400 MG Oral Tablet brand · RxCUI 602407 | 7 (2%) | 4 | 1 | 0 | 0 |
| Horizant 300 MG Extended Release Oral Tablet brand · RxCUI 1482821 | 4 (1%) | 4 | 0 | 0 | 0 |
| Horizant 600 MG Extended Release Oral Tablet brand · RxCUI 1101339 | 4 (1%) | 4 | 0 | 0 | 0 |
| Gralise 300 MG Once-Daily Oral Tablet brand · RxCUI 1115012 | 1 (0%) | 4 | 1 | 0 | 1 |
| Gralise 450 MG Once-Daily Oral Tablet brand · RxCUI 2634749 | 1 (0%) | 4 | 1 | 0 | 1 |
| Gralise 600 MG Once-Daily Oral Tablet brand · RxCUI 1115013 | 1 (0%) | 4 | 1 | 0 | 1 |
| Gralise 750 MG Once-Daily Oral Tablet brand · RxCUI 2634753 | 1 (0%) | 4 | 1 | 0 | 1 |
| Gralise 900 MG Once-Daily Oral Tablet brand · RxCUI 2634745 | 1 (0%) | 4 | 1 | 0 | 1 |
| Neurontin 100 MG Oral Capsule brand · RxCUI 105028 | 1 (0%) | 1 | 0 | 0 | 1 |
| Neurontin 250 MG in 5 mL Oral Solution brand · RxCUI 351973 | 1 (0%) | 1 | 0 | 0 | 1 |
| Neurontin 300 MG Oral Capsule brand · RxCUI 105029 | 1 (0%) | 1 | 0 | 0 | 1 |
| Neurontin 400 MG Oral Capsule brand · RxCUI 105030 | 1 (0%) | 1 | 0 | 0 | 1 |
| Neurontin 600 MG Oral Tablet brand · RxCUI 261280 | 1 (0%) | 1 | 0 | 0 | 1 |
| Neurontin 800 MG Oral Tablet brand · RxCUI 261281 | 1 (0%) | 1 | 0 | 0 | 1 |
Counts are formularies (of 328) in the CMS file that list the form, and how many of those apply prior authorization (PA), step therapy (ST) or a quantity limit (QL). Many plans share one formulary, so plan counts in a county will differ.
How to read drug coverage
Tier is the cost-sharing tier the plan assigned the drug in its CMS formulary filing; lower tiers usually cost less. PA = prior authorization, ST = step therapy (try another drug first), QL = quantity limit. Not on formulary means the plan did not list this exact form; the plan may cover another strength or a formulary exception may be possible. Cost sharing is the plan's initial-coverage amount for the tier as filed with CMS; the deductible, the $2,100 annual out-of-pocket cap, the $35 insulin cap and negotiated prices for selected drugs can change what you actually pay. Formularies change during the year; the plan's formulary document and Medicare.gov govern.
What the star rating under each Medicare Advantage plan means
What the star rating means. CMS rates every Medicare Advantage contract (the "H" number in the plan ID — all plans under it share the rating) on a 1-to-5 scale each October, from about 40 measures of care quality, member experience, complaints and appeals, customer service and, for plans with drug coverage, drug safety and pricing. The 2026 rating is largely based on performance measured in 2024.
5 Excellent4 Above average3 Average2 Below average1 Poor
Not rated means CMS published no overall rating — usually a contract too new to be measured or with too few members ("not enough data"); it is not a low score. A 5-star contract can be joined outside the normal enrollment windows (the 5-star Special Enrollment Period, Dec 8 – Nov 30). Medicare.gov flags contracts rated below 3 stars for three years running as low-performing. Stars describe the contract's past performance as CMS measured it; they are not a recommendation, and they do not tell you whether a plan's network, drugs or costs fit you.