Two medicines, side by side
Methocarbamol vs tizanidine
Methocarbamol and tizanidine are both labeled for muscle spasms and spasticity. Drugs@FDA records approvals of methocarbamol since 1957 and of tizanidine since 1996. Pharmacies paid $0.0395 per methocarbamol 500 mg tablet and $0.0331 per tizanidine HCl 4 mg tablet (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like. In FDA's classes, methocarbamol is a muscle relaxant and tizanidine a central alpha-2 adrenergic agonist.
Check it at the source: the methocarbamol FDA label on DailyMed (effective March 17, 2026); the tizanidine FDA label on DailyMed (effective January 2, 2026).
Highlights of the methocarbamol record
Methocarbamol (Robaxin) · label of March 17, 2026
Used for
From the label: indicationsMethocarbamol is indicated as an adjunct to rest, physical therapy, and other measures for the relief of discomfort associated with acute, painful musculoskeletal conditions. The mode of action of methocarbamol has not been clearly identified, but may be related to its sedative properties. Methocarbamol does not directly relax tense skeletal muscles in man.
On the market
- Earliest approval on file
- July 16, 1957
- Generic labelers
- 65 labelers
- Pharmacy cost
- $0.0395 per tablet
Supply and safety
- Shortage
- No current entry
- Recalls
- 6
Highlights of the tizanidine record
Tizanidine (Zanaflex) · label of January 2, 2026
Used for
From the label: indicationsZanaflex is indicated for the treatment of spasticity in adults. Zanaflex is a central alpha-2-adrenergic agonist indicated for the treatment of spasticity.
On the market
- Earliest approval on file
- November 27, 1996
- Generic labelers
- 49 labelers
- Pharmacy cost
- $0.0331 per tablet
Supply and safety
- Shortage
- No current entry
- Recalls
- 9
Source: FDA drug labels via openFDA (Methocarbamol label of March 17, 2026, Tizanidine label of January 2, 2026); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do methocarbamol and tizanidine differ on the record?
In FDA's classes, methocarbamol is a muscle relaxant and tizanidine a central alpha-2 adrenergic agonist.
How each works, in its label's words: Methocarbamol, “of methocarbamol in humans has not been established, but may be due to general central nervous system (CNS) depression.”; Tizanidine, “Tizanidine is a central alpha-2-adrenergic receptor agonist and presumably reduces spasticity by increasing presynaptic inhibition of motor neurons.”
Half-life, in each label's words: Methocarbamol, “Pharmacokinetics In healthy volunteers, the plasma clearance of methocarbamol ranges between 0.20 and 0.80 L/h/kg, the …”; Tizanidine, “Elimination Metabolism Tizanidine has a half-life of approximately 2.5 hours (CV=33%).”
Generics: methocarbamol since 1974; tizanidine since 2002 (Drugs@FDA).
| Methocarbamol | Tizanidine | |
|---|---|---|
| Labeled for | Muscle spasms and spasticity | Muscle spasms and spasticity |
| Pharmacologic class | Muscle Relaxant | Central alpha-2 Adrenergic Agonist |
| How it works (label) | of methocarbamol in humans has not been established, but may be due to general central nervous system (CNS) depression. It has no direct action on the contractile mechanism of striated muscle, the motor end plate or the nerve fiber. | Tizanidine is a central alpha-2-adrenergic receptor agonist and presumably reduces spasticity by increasing presynaptic inhibition of motor neurons. The effects of tizanidine are greatest on polysynaptic pathways. |
| Half-life (label) | Pharmacokinetics In healthy volunteers, the plasma clearance of methocarbamol ranges between 0.20 and 0.80 L/h/kg, the mean plasma elimination half-life ranges between 1 and 2 hours, and the plasma protein binding … | Elimination Metabolism Tizanidine has a half-life of approximately 2.5 hours (CV=33%). |
| Earliest approval on file (Drugs@FDA) | July 16, 1957 | November 27, 1996 |
| First generic approved | October 22, 1974 | June 27, 2002 |
| Generic labelers (NDC) | 65 labelers | 49 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $0.0395 per tablet (Methocarbamol 500 mg tablet) | $0.0331 per tablet (Tizanidine HCl 4 mg tablet) |
| 12-month price change | +6% | -12% |
| Boxed warning | No | No |
| Shortage now | No current entry | No current entry |
| Recalls recorded | 6 | 9 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 22,591 | 41,179 |
| DEA schedule | none | none |
Source: Drugs@FDA, FDA NDC Directory, CMS NADAC of October 7, 2026, FDA shortages and recalls, FAERS via openFDA (FDA files October 8, 2026)
What do the labels say about using others of their kind?
Methocarbamol label, warningsWARNINGS Since methocarbamol may possess a general CNS depressant effect, patients receiving methocarbamol tablets should be cautioned about combined effects with alcohol and other CNS depressants.
Source: FDA drug labels via openFDA
What next?
- Alternatives to methocarbamol
- every medicine labeled for the same conditions