spierrelaxantia

Spierrelaxantia, or muscle relaxants, are medicines that reduce skeletal muscle tone. They are used to relieve muscle spasticity, cramps, and painful muscle spasms, and may be prescribed for acute musculoskeletal pain. They work by either suppressing central nervous system activity or acting directly on muscle or neuromuscular transmission.

Mechanisms and types: Central acting drugs include baclofen (a GABA-B agonist), diazepam, and tizanidine (an alpha-2 adrenergic agonist). Other centrally acting agents such as methocarbamol, cyclobenzaprine, chlorzoxazone, and orphenadrine are used for short-term relief of acute muscle strain. Peripheral acting agents include dantrolene, which decreases calcium release in muscle cells, and botulinum toxin, which inhibits acetylcholine release at the neuromuscular junction for focal spasticity.

Indications: Spasticity from neurological conditions such as spinal cord injury, multiple sclerosis, or stroke; muscle cramps and localized painful spasms. Botulinum toxin injections are used for targeted, focal muscle overactivity, while intrathecal baclofen is used for severe generalized spasticity.

Administration and dosing: Central agents are typically taken orally; botulinum toxin is injected into specific muscles; intrathecal baclofen is delivered via an implanted pump.

Adverse effects and precautions: Common side effects include drowsiness, dizziness, and weakness. Sedation and cognitive impairment can affect daily functioning; benzodiazepines carry risks of dependence. Dantrolene can cause liver toxicity; drug interactions are important (for example, tizanidine interactions with certain antibiotics and antidepressants). Spierrelaxants can worsen muscle weakness in myasthenia gravis and should be used with caution in the elderly. They are usually part of a broader treatment plan that includes physical therapy and rehabilitation.

Note: This overview is informational; specific treatment should be guided by a clinician.