FDA pharmacologic class
Muscle relaxants
6 medicines are in FDA's class of muscle relaxants (muscle relaxants): cyclobenzaprine (Amrix), methocarbamol (Robaxin), metaxalone, carisoprodol (Soma), chlorzoxazone and orphenadrine; 1 combination product also contains one. All 7 are listed from generic labelers (FDA NDC Directory, October 8, 2026). The lowest pharmacy cost is cyclobenzaprine 10 mg tablet at $0.0171 per tablet (NADAC).
Which medicines are muscle relaxants?
| Medicine | Brand names | Generic labelers (all forms) | Pharmacy cost | Boxed warning | Shortage | Recalls since 2012 |
|---|---|---|---|---|---|---|
| Cyclobenzaprine | Amrix, Tonmya, Fexmid | 59 labelers | $0.0171 per tablet 10 mg tablet | No | No current entry | 5 |
| Methocarbamol | Robaxin, Atmeksi, Tanlor | 65 labelers | $0.0395 per tablet 500 mg tablet | No | No current entry | 6 |
| Metaxalone | none listed | 33 labelers | $0.452 per tablet 800 mg tablet | No | No current entry | 0 |
| Carisoprodol | Soma | 24 labelers | $0.0706 per tablet 350 mg tablet | No | No current entry | 5 |
| Chlorzoxazone | none listed | 19 labelers | $0.210 per tablet 500 mg tablet | No | No current entry | 2 |
| Orphenadrine | none listed | 17 labelers | $0.454 per tablet 100 mg tablet | No | No current entry | 3 |
| Aspirin and caffeine and orphenadrine | Norgesic, Orphengesic | 3 labelers | n/a | No | No current entry | 0 |
Source: FDA Established Pharmacologic Class (NDC Directory, openFDA); CMS NADAC of October 7, 2026; FDA shortages and recalls (FDA files October 8, 2026)
What do pharmacies pay?
Each medicine's most widely listed form, per unit, in the NADAC survey: what pharmacies paid, not what a patient pays; strengths differ, so compare like with like.
Source: CMS National Average Drug Acquisition Cost (NADAC) survey, October 7, 2026: what retail pharmacies paid per unit; not a counter price