Levodopa Bromocriptine

Opioids, benzodiazepines, barbiturates, corticosteroids, dopamine agonists (e.g., amantadine, bromocriptine, levodopa, pergolide, pramipexole, ropinirole), H2-receptor antagonists, anticholinergics (e.g., diphenhydramine, trihexylphenidyl), P-adrenergic blockers, clonidine, methyldopa, carbamazepine, phenytoin, baclofen, cyclobenzaprine, lithium, antidepressants (e.g., tricyclic antidepressants, selective serotonin reuptake inhibitors), and interleukin-2... 

DOPAMINERGICS PARACETAMOL Amantadine, bromocriptine, levodopa, pergolide, pramipexole and selegiline may slow the onset of action of intermittent-dose paracetamol Anticholinergic effects delay gastric emptying and absorption Warn patients that the action of paracetamol may be delayed. This will not be the case when paracetamol is taken regularly... 

The drug is contraindicated in patients with a history of psychosis The drug should not be administered to patients already taking levodopa Mental disturbances occur more commonly with levodopa than with bromocriptine A 72-year-old patient with parkinsonism presents with swollen feet. They are red, tender, and very painful. You could clear up these symptoms within a few days if you told the patient to stop taking (A) Amantadine Benztropine Bromocriptine Levodopa Selegiline... 

Parkinsonian patients receiving the dopamine precursor, levodopa or dopamine receptor agonists, such as bromocriptine and apomoiphine may experience nausea and vomiting due to stimulation of dopamine D2 receptors in the CTZ. 

Another indication of the importance of DA in motor control is the observation that in humans its precursor levodopa, and DA agonists like bromocriptine, not only overcome the akinesia of Parkinsonism but in excess will actually cause involuntary movements, or dyskinesia (Chapter 14). Also it is well known that DA antagonists like chlorpromazine and haloperidol produce Parkinsonian-like symptoms in humans (and catalepsy in animals) and, as indicated above, reduce the dyskinesia of Huntington s Chorea. Thus DA seems to sit on a knife edge in the control of motor function (Fig. 7.8). 

Dopamine-Boosting Medications. Levodopa/carbidopa (Sinemet), bromocriptine (Parlodel), pramipexole (Mirapex), and ropinirole (Requip) increase dopamine nenrotransmission in the brain by one or another mechanism. These medications do not reliably induce sleep, and in some patients are activating. They are certainly not true sedative-hypnotics. They are most often used by neurologists to treat Parkinson s disease. 

Chlorpromazine is an aliphatic phenothiazine antipsychotic used in schizophrenia and which may exacerbate parkinsonism. Co-careldopa is a combination of levodopa and the peripheral dopa-decarboxylase inhibitor, carbidopa. Co-careldopa, amantadine, entacapone and bromocriptine are all indicated in the management of parkinsonism. 

Bromocriptine is a dopamine agonist acting by direct stimulation of the dopamine receptors. In Parkinson s disease, it is reserved for use in patients who are intolerant to levodopa or in whom levodopa alone is not sufficient. Orphenadrine is an antimuscarinic indicated in Parkinson s disease. Antimuscarinics tend to be more effective than levodopa in targeting tremor rather than rigidity and bradykinesia. Moclobemide is an antidepressant referred to as a reversible monoamine oxidase inhibitor (RIAAA) type A. 

Dopamine receptor agonists. Deficient dopaminergic transmission in the striatum can be compensated by ergot derivatives (bromocriptine p. 114], lisu-ride, cabergoline, and pergolide) and nonergot compounds (ropinirole, prami-pexole). These agonists stimulate dopamine receptors (D2, D3, and D sub-types), have lower clinical efficacy than levodopa, and share its main adverse effects. 

In medical practice, four types of dopaminergic drags are used, and they can be characterized as dopamine precursors (levodopa), dopamine-releasing drugs (amantadine), dopamine receptor agonists (bromocriptine), and dopamine inactivation inhibitors (selegiline). 

Benztropine (Cogentin) Bromocriptine (Parlodel) Carbidopa/Levodopa (Parcopa, Sinemet)... 

Clarke CE, SpeUer JM. Pergolide versus bromocriptine for levodopa-induced complications in Parkinson s disease. Cochrane Database Syst Rev 1999. 

Adjunct to levodopa/carbidopa in Parkinson s disease longer acting than bromocriptine... 

At least as effective as bromocriptine in the treatment of advanced parkinsonian patients with levodopa-related motor fluctuations adverse effects similar in incidence and severity appears to lack some of the toxicity seen with bromocriptine, pergolide, and cabergoline (e.g., pleuropulmonary disease) may be a useful alternative in patients with intolerable adverse effects due to ergot derivatives... 

Dopamine agonists suppress prolactin release very effectively in patients with hyperprolactinemia. GH release is reduced in patients with acromegaly, although not as effectively. Cabergoline and bromocriptine are also used in Parkinson s disease to improve motor function and reduce levodopa requirements (see Chapter 28). Newer, nonergot D2 agonists... 

Bromocriptine (Parlodel) (Azilect) Carbidopa/Levodopa Ropinirole (Requip)... 

Dopamine agonists Bromocriptine Cabergoline Pergolide Pramipexole Ropinirole Directly stimulates dopamine receptors in basal ganglia. May produce fewer side effects (dyskinesias, fluctuations in response) than levodopa preliminary evidence suggests that early use may also delay the progression of Parkinson disease. 

Later, the disease does not respond to the drug and doses are required to be given in combination with carbidopa. Levodopa is effective in relieving bradykinesia and other disorderly voluntary movements. Parkinson s disease is not a hereditary disease. Drugs such as levodopa, carbidopa, benserazide, bromocriptine, pergolide, selegiline, and amantadine are used as therapeutic agents.61... 

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