Notes for: Skeletal Muscle RelaxantsLast edited [21/08/2013 15:50:47]
1. The underlying cause of spasticity should be treated and any aggravating factors (eg pressure sores, infection) treated.
2. Dantrolene acts directly on skeletal muscle and produces fewer central adverse effects making it a drug of choice. Liver function should be tested before and at intervals during therapy.
3. Baclofen inhibits transmission at spinal level and also depresses the central nervous system.
4. Tizanidine is a newly introduced drug which should only be initiated by a Specialist familiar with its use.
5. Diazepam (section 4.1.2) may also be used. Sedation and, occasionally, extensor hypotonus are disadvantages.
6. See MHRA Drug Safety Update June 2010 on quinine which is not a routine treatment for nocturnal leg cramps, and should only be used when cramps regularly disrupt sleep.
After a trial of at least 4 weeks, treatment should be stopped if there is no benefit. If treatment continues, the benefits should be assessed around every 3 months.
Patients should be monitored closely during the early stages for adverse effects as well as for benefit.
Treatment should be interrupted at intervals of approximately 3 months to assess the need for further quinine treatment.
Patients should be warned not to exceed the recommended dose. Serious side effects including irreversible blindness and death may occur with overdose.
Thrombocytopenia is a rare but potentially life-threatening adverse reaction associated with quinine. Patients should be instructed to stop treatment and consult a physician if signs of thrombocytopenia occur, such as unexplained petechiae, bruising, or bleeding.