DYSFUNCTIONS
Dyskinesias are generally described as involuntary abnormal movements in any patient. Especially in patients with Parkinson's disease, dyskinesias are associated with the use of drugs and are divided according to the form they take and the time of taking the anti-parkinsonian drugs. They usually occur in patients with a good response to levodopa and the incidence is higher in patients with early onset of the disease. The main types of dyskinesias are:
PEAK-DOSE DYSKINESIAS
These automatic movements occur when the drug is at its maximum concentration in the patient's blood serum. They are twisting movements, like dancing, non-standardized usually in the upper and lower limbs but also in the trunk and head. They disappear when levodopa levels fall in the patient's blood.
WEARING-OFF DYSTONIA
These movements, on the contrary, appear when the levels of levodopa in the blood plasma have fallen, so mainly at night or in the morning before the first dose of the drug. It is usually a painful spasm in the muscles of the lower limbs. They improve with the administration of dopamine agonists or slow-release preparations of levodopa.
DIPHASIC DYSTONIA/DYSKINESIA
These moves are relatively rare. Both forms occur when a patient with Parkinson's disease is in the phase of good response to levodopa and then goes into the phase where the drug's effect wears off when taking the same levodopa tablet. Here too there are usually dance-like movements alternating with dystonia and it usually involves the lower limbs. In general, this type of dyskinesia is very difficult to treat and the best treatment is probably surgical treatment.
50% of patients receiving more than 5 years of levodopa show such dyskinesias. This percentage reaches 90% in patients receiving levodopa for more than 15 years.