Dystonia
An approach to symptom management to guide decision-making in the management of patients with life-threatening illness
Explanation to patient and family
Consider adjuvant/second line treatment
Description
Dystonia is a sustained muscle contraction causing twisting and repetitive movements or abnormal postures. Examples include torticollis and facial spasms, trismus of the jaw, grimacing, gaping, tongue protrusion, oculogyric crisis and opishotonus. Dystonia is often associated with anxiety.
Tardive dyskinesia is a form of dystonia caused by the long term effects of drugs that block dopamine receptors. It manifests as involuntary repetitive purposeless body movements such as grimacing, tongue protrusion, lip smacking, puckering of lips and rapid eye blinking. Tardive dyskinesia can unfortunately be a permanent adverse effect of neuroleptics (e.g. chlorpromazine), dopamine antagonists (e.g. haloperidol) and metoclopramide.
Appropriate assessment to identify cause and severity of symptoms.
Causes of dystonia
In Palliative Care dystonias are often related to the extra-pyramidal side effects of commonly used drugs such as the phenothiazines e.g. chlopromazine, metoclopramide and dopamine antagonists e.g haloperidol.
Acute dystonias occur in up to 10% of patients on neuroleptic drugs. They develop abruptly within days of starting oral treatment and within minutes of an intravenous injection.
Dystonias can also be caused by brain damage, infection, chemical imbalances, toxins and poisoning.
Primary dystonias also occur in the general population.
Explanation to patient and family
Acute onset of dystonia can be very distressing for the patient and family. Explanation as to the nature and possible causes of dystonia will help reduce fear and anxiety. Unfortunately some drug-induced dystonias e.g. tardive dyskinesia are irreversible (especially in the elderly) and the patient/family need to be prepared for this possibility. Explain that the causative drug will be reduced or stopped and that everything possible will be done to alleviate the symptom. Ensure that the family/patient are aware that the treatments are often sedating and are often unsatisfactory.
Correct reversible factors
Discontinue causal drug. Substitute if necessary, e.g. use domperidone rather than metoclopramide. Always be vigilant when prescribing neuroleptic drugs in palliative care especially when combined with anti-emetics, metoclopramide or haloperidol. Do not combine metoclopramide with halpoperidol!
Institute non-pharmacological interventions by involvement of the interdisciplinary team.
- Dystonia is often accompanied by anxiety and involvement of the psychosocial team should be considered.
- Consult with the pharmacist involved if necessary to discuss drug doses and interactions as well as alternative drugs.
- Acupuncture has been effective in the treatment of some dystonias.
- Consider physiotherapy with tactile pressure and massage.
Pharmacological interventions
- Benzodiazepines e.g. clonazepam 0.5 mg po bd (alternately lorazepam 1mg po tds or diazepam 10 mg nocte)
- Baclofen 10-20 mg bd-tds
- Diphenhydramine 20-50 mg iv/im for acute severe dystonia, repeat after 20-30 minutes if necessary. Then 25-50 mg po bd-qid
Start all drugs at a low dose and slowly increase until symptom is controlled or intolerable adverse effects occur. Results are often poor or inconsistent.
Consider adjuvant/second line treatment
- Anti-Parkinson's drugs e.g. carbidopa/levodopa, ropinirole
- Injection of Botulinus toxin Type A into the dystonic muscles in specific cases e.g. blepharospasm, torticollis, hemifacial spasm and other focal dystonias (this is only to be administered by an experienced practitioner)