Pergolide is an ergot derivative commonly used for the treatment of Parkinson’s disease. Patients may take the medication alone or in conjunction with levodopa/carbidopa combinations. The Parkinson's medication is associated with multi-system side effects, including heart valve damage. It was withdrawn from the U.S. market because of the large number of patients experiencing this serious adverse reaction.
The anti-Parkinsonian effects of pergolide occur as the medication attaches to the synaptic dopamine receptors in the brain. The binding stimulates dopamine production in the nigrostriatal pathways. It is the loss of dopamine from these pathways that produces the pathological features of Parkinson’s. The drug also inhibits prolactin secretion, causes a temporary rise of growth hormone blood levels, and temporarily decreases the levels of luteinzing hormone.
In addition to Parkinson’s disease, pergolide may be prescribed as treatment for hyperprolactinemia or restless leg syndrome. Parkinson’s patients taking the medication along with dopamine substitutes may have dopamine levels increased by up to 30%. The dopamine receptor agonist effect of the formulation may allow some patients to reduce or discontinue other medications.
After entering the body, 90% of pergolide binds with proteins, and this action may interfere with other protein binding medications. Pergolide should not be used in combination with dopamine antagonists, as the medications generally render each other inactive. The medication also binds to certain serotonin receptor cells located throughout the body, producing a number of adverse effects.
Pergolide may cause postural hypotension and peripheral edema, and patients may also experience premature atrial contractions or sinus tachycardia. Cardiac valve damage has occurred due to inflammatory responses or fibrosis. These adverse reactions might also contribute to pleuritis, pleural effusions, and pneumonia. Common respiratory side effects also include runny nose and cough.
Serious central nervous system reactions include patients falling asleep without having a prior feeling of drowsiness. This effect becomes potentially dangerous when individuals taking pergolide operate motorized vehicles or mechanical equipment. Patients also complain of experiencing confusion, double vision, and hallucinations.
Some individuals display dyskinesia, a condition associated with involuntary, repetitive movements. People with dyskinesia may exhibit constant lip smacking or appear to roll a pill between the thumb and index finger. the condition can also produce constant blinking, tongue protrusion, or walking with a shuffled gait.
Individuals using prescription pergolide commonly experience diarrhea or constipation and nausea along with abdominal discomfort. Many complain of generalized pain similar to the discomfort accompanying arthritis. Sudden weight gain and loss due to edema can also occur.