Recently patients have been asking about Apomorphine as a miracle drug to treat Parkinson’s disease. It is necessary to explain to them the merits and demerits of the drug.

The complex coordinated movement in a human body happens through an interaction between the cerebral cortex, basal ganglia and cerebellum.any disturbance in the interaction will cause movement disorders. There are many neural transmitters that are responsible for the coordinated movements and dopamine is one among them. In Parkinson’s disease, symptoms are caused by the slow and steady loss of dopaminergic neurons (those secreting dopamine) at several areas of brain including Substantia Nigra. People with Parkinson’s don’t have enough dopamine. This lack of dopamine causes the symptoms of Parkinson’s.

Drugs used to treat symptoms of Parkinson’s Disease are called Dopamine agonist drugs. Until recently all the drugs were administered orally. Apomorphine is a strong type of dopamine agonist and act like dopamine to stimulate nerve cells. These nerve cells then control movement and other body functions, to help reduce the symptoms of Parkinson’s. Although apomorphine does not contain morphine, it is derived from it (has no morphine like activity). Unlike other dopamine agonist drugs, which are taken as tablets or patches, apomorphine is given by injection or continuous infusion, using a pump.

Symptoms from Parkinson’s disease vary from patient to patient and hence the treatment will also vary. Even for the same patient symptoms could change over a period of time and hence the medication may have to be changed. Apomorphine is usually used when a person’s symptoms no longer respond well to oral drug treatments. However they may not work on every patient and it may not replace oral medication entirely.

“Off” and “On” periods of Parkinson’s disease
When Parkinson’s symptoms are controlled by drugs, it is said to be in the “On” period and when symptoms are not controlled or the action of the drug is wearing off, it is in the “Off” period.

Apomorphine may be a useful drug during the “Off” period under two circumstances. One, when the oral drugs to treat Parkinson’s disease is wearing off more quickly and the next dose would take time to act (as it has to be absorbed from the gut before it can reach the bloodstream) or when some unpredictable changes in symptoms are seen. Apomorphine may be useful at this time as it is an injection and its action will be swift . 2, When the disease gets refractory to the action of usual drugs and symptoms are not controlled effectively, the apomorphine injection may come in handy to control the symptoms quickly. It would also be a good alternative when patients are unable to swallow oral medication.

Administration:
Apomorphine is administered through a “pre-filled disposable pen” and injected subcutaneously as and when required. It usually take 5 to 10 minutes to act and can be injected several times during the day when the patient is awake. The effect may last for 40 to 60 minutes when the oral medication may come in to effect. In more severe cases requiring continuous medication it is given as a continuous infusion through a syringe pump. It should not be given intravenously.

Side Effects:
It could cause skin reaction, drowsiness, dizziness or confusion. Hallucinations, nausea, or vomiting is also reported.
Other side effects are dyspnoea, haemolytic anaemia, thrombocytopenia, postural hypotension and palpitation.
Rare side effects are bronchospasm, eosinophilia, hypersensitivity, aggression, impulsive and compulsive disorders and syncope.

Also Read the full article on Parkinson’s disease that was discussed a few years ago on http://www.tnmgc.com/discus/viewtopic.p … p=508#p508