| Term | Description |
| Dystonia. | small involuntary movements characterized by muscle cramps. Dystonia is a syndrome of sustained muscle contractions, frequently causing twisting and repetitive movements, or abnormal postures. Dystonias are often accompanied by pain, e.g. stiff neck or torticollis is a form of dystonia. Other forms of dystonias are an oculogyric crisis, retrocollis, trismus, opisthotonos, or laryngospasm. These reactions can be life-threatening if left untreated. Treatment: IV or IM anticholinergic agents (e.g., benztropine, diphenhydramine) |
| Dyskinesia | small involuntary movements that are like small ticks. Tardive dyskinesia (TD), estimated to occur in 30% of patients treated with neuroleptics, encompasses a broad spectrum of hyperkinesias associated with exposure to these drugs. |
| Akinesia. | “Akinesia refers specifically to lack of movement, such as loss of arm swing, but is also used to mean slowing (bradykinesia) or reduction (hypokinesia) in the size of movements. Akinesia affects mainly the hands or the trunk and walking.” It’s caused by muscle rigidity. Often begins in the legs and neck. These muscles become very stiff. When it affects the muscles of the face the individual adopts a mask-like stare. |
| Bradykinesia | slowness of motion. The individual’s movements become increasingly slow and over time muscles may randomly “freeze”. |
| Akathisia. | Akathisia is “a feeling of inner restlessness that can be manifested as excessive pacing or inability to remain still for any length of time.” It’s often difficult to distinguish between akathisia and psychiatric anxiety and agitation.
Thefreedictionary.com: “the inability to sit still because of uncontrollable movement caused by reaction to drugs”
[C20: from a- + -kithisia, ultimately from Greek cathedra seat]
Treatment: Reduce the dose of the antipsychotic medication. Add a low dose beta blocker, e.g. Propranolol 20 to 80 mg PO daily. |
The terms Hypokinesia, akinesia, bradykinesia are also frequently used in cardiology to describe the movement of the heart muscle on an echocardiogram.
Reference
Psychiatr Clin North Am. 1997 Dec;20(4):821-38. https://www.ncbi.nlm.nih.gov/pubmed/9443352
Am Fam Physician. 2010 Mar 1;81(5):617-622. http://www.aafp.org/afp/2010/0301/p617.html
https://www.parkinsonswa.org.au/what-is-parkinsons/