Key takeaways
Tizanidine (Zanaflex) and dantrolene (Dantrium) are both muscle relaxants, but they work differently and are used for different conditions. Tizanidine is an alpha-2 adrenergic receptor agonist that slows down nerves in your spinal column to relax muscles, and it's typically used for muscle stiffness and rigidity. On the other hand, dantrolene's exact mechanism isn't fully understood, but it is thought to block the release of calcium in muscles, preventing them from contracting. Dantrolene is used for long-term muscle spasticity. Tizanidine is taken by mouth up to three times a day, while dantrolene is taken three to four times a day. Dantrolene is also available as an injection, which is used in the hospital for preventing or treating malignant hyperthermia during surgery. Tizanidine can cause side effects like low blood pressure, dry mouth, and sleepiness, whereas dantrolene can cause liver problems, dizziness, and diarrhea. Both medications are available in generic forms and are not controlled substances.
