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Advanced Neurology Piribedil for Parkinson’s disease

the latter had a higher risk of drug withdrawal due to well tolerated by patients and family members, they may
gastrointestinal adverse events . not need to be actively treated, or a reduction of the drug
[38]
Piribedil-induced gastrointestinal tract reactions are dose that might have triggered psychosis syndrome can be
short-term conditions and tend to disappear gradually. The considered under the guidance of experts. For PD patients
undesired effect can be relieved by dose titration control without cognitive disorder, quetiapine may be used for
or by administration of food. If the symptoms cannot be the treatment of hallucination and delusion, although
relieved, then domperidone, a peripheral DR inhibitor, the risk of deterioration in motor function cannot be
could be used, but it is prohibited in patients with excluded. If standard therapy failed, clozapine may be
arrhythmia due to the risk of CT interval prolongation . considered by carefully monitoring the blood cell count.
[56]
Olanzapine or other antipsychotic drugs (phenothiazines
4.2. Daytime somnolence and sleep attack or butyrophenones) are not recommended because they
may result in confused symptoms or deterioration of
As piribedil has α2-adrenoreceptor antagonistic effects, its parkinsonian motor symptoms . Bromocriptine is not in
[14]
incidence of daytime somnolence might be lesser than that of use anymore because it is an ergot derivative.
other DR agonists. The incidence of piribedil-related daytime
somnolence is approximately 2% to 30%; however, it rarely 4.4. Hypotension orthostatic
results in drug withdrawal . In over 30 years of clinical use,
[12]
few cases of sudden sleep onset associated with piribedil Hypotension orthostatic is common at the onset of therapy
have been reported. A position statement from the European and caused by the agonistic effect on DA receptors at the
Medicines Agency on sleep events and dopaminergic presynaptic level of the orthosympathetic system, and
medications indicated that piribedil is “very rarely” associated usually becomes tolerable over time. It mainly occurs in
st
with the incidences of excessive daytime somnolence . the 1 week after the use of piribedil, accounting for 5% of
[30]
[58,59]
A RCT showed that in patients with PD who developed the adverse drug reactions .
daytime somnolence on pramipexole or ropinirole, switching Animal experiments showed that intravenous injection of
to piribedil significantly reduced daytime somnolence piribedil may decrease hypertension and heart rate . During
[30]
compared with those continued on original treatment . the clinical use of piribedil, decreased systolic pressure and a
[44]
Patients should be informed of the potential adverse slight decrease of heart rate and body temperature may also
[29]
reactions. Caution must be taken while driving or occur especially in patients with advanced PD .
operating the machine and while taking this drug. Those The antihypertensive drug history should be traced,
who have experienced this adverse reaction should avoid including antihypertensive drugs (including diuretics),
driving or operating the machine, and consider to reduce dopaminergic drugs, alpha-blockers, and antidepressant
the dose or discontinue the treatment. It is suggested to drugs. These drugs may be tapered or stopped, if
reduce the dose to achieve satisfying response, keep sleep possible. Midodrine, an alpha-1 agonist, could be used.
hygiene, and treat actively, if necessary, with modafinil or If there are contraindications for midodrine, using the
amantadine drugs [14,57] . mineralocorticoid fludrocortisone can be considered;
however, attention should be paid to cardiac risk factors .
[14]
4.3. Neuropsychiatric disorders
Droxidopa is “clinically useful” for the short-term
Piribedil-induced neuropsychiatric disorders, such as treatment of orthostatic hypotension, whereas no data from
psychosis and hallucination, have an incidence of 4 – RCTs on treating PD with droxidopa for a longer treatment
23% and are more frequent in patients with preexisting time are available . If there are concurrent cardiovascular
[60]
cognitive deficits . This phenomenon may be dose- reactions, such as heart rate change, it is suggested to stop
[12]
dependent, and elderly and advanced patients with PD medication and adopt fluid infusion measures . Other
[59]
are at a higher risk . Hallucination is a major cause for patient’s management includes education, advice and
[30]
drug withdrawal . However, a double-blind RCT showed training on factors influencing blood pressure, and special
[39]
that there was no significant difference in the incidence of aspects to be avoided (i.e., foods, habits, and positions).
neuropsychiatric disorders through 7-month treatment of Physical measures include leg crossing, squatting, elastic
piribedil compared with placebo . As only 35 patients abdominal binders, and stockings. Furthermore, careful
[57]
were enrolled in this trial, the insignificant results may be exercise will improve the orthostatic hypotension .
[61]
due to insufficient power.
It is not recommended for the elderly patients with 4.5. Impulse-control disorders
neuropsychiatric symptoms to take piribedil if they have Impulse-control disorders (ICDs) occur in 2% to 13.7% of
never used piribedil. If neuropsychiatric symptoms are patients with PD and are more prevalent at a high dose;

Volume 2 Issue 1 (2023) 9 https://doi.org/10.36922/an.290