Answer: Duodopa® consists of the active substances L-dopa (L-3,4-dihydroxyphenylalanine, levodopa) and carbidopa in a carboxymethyl cellulose and water gel. L-dopa is a neutral amino acid that is converted into dopamine by the dopa-decarboxylase enzyme. Carbidopa inhibits the enzyme action peripherally, i.e. outside the brain, allowing the largest amount possible of the L-dopa to reach the brain. The active substances are exactly the same as in Sinemet®. Madopar® contains a different decarboxylase inhibitor. Carboxymethyl cellulose is a form of thickener used in food products.
Question: How does Duodopa® differ from the other antiparkinsonian medicines?
Answer: Duodopa® contains the same substances as Sinemet® and practically the same as Madopark®, the difference being that Duodopa® is administered continuously and directly to the upper part of the small intestine where it can be absorbed into the blood. In this way the uptake, transport to the brain, and conversion into dopamine all run evenly throughout the day. L-dopa is considered the most effective of all antiparkinsonian drugs.
Question: What symptoms is Duodopa® best at counteracting?
Answer: Duodopa® first and foremost counteracts the typical Parkinson’s-disease symptoms, i.e. tremor, stiffness and slowed down body movements. The most common side effect in progressive disease is involuntary movements of the body. Duodopa® treatment minimizes involuntary body movements by keeping the L-dopa concentration relatively constant. As long as the pump is active it maintains a sufficiently high concentration of L-dopa (and dopamine) to counteract symptoms of Parkinson’s disease. This means that motor function can be kept at a stable level and at best even avoid off-periods. Sometimes symptoms can appear despite a steady supply of L-dopa, for example during periods of stress, worry, or at meal times (see below). However, these off-periods are often transitory and mild.
Question: Can Duodopa® be effective against other symptoms than tremor, stiffness and slowed down body movements?
Answer: Many different symptoms may show in Parkinson’s disease. It is not possible to generalize about which symptoms may be counteracted by Duodopa® but theoretically it has the same therapeutic effects as L-dopa tablets. There is experience showing that continuous administration of medicine can be beneficial in different ways, in addition to the stabilizing effect it has on motor function. Some patients experience improved motor function during the night (even though the pump is turned off), and some report that their ability to concentrate has improved. A normal observation is that all people with Parkinson’s disease have different combinations of symptoms and are affected differently by their symptoms. Similarly people have many individual experiences of the effects of Duodopa®.
Question: What side effects can Duodopa® cause?
Answer: Duodopa® consists of the same active components as L-dopa tablets and as such both treatments can give the same side effects. The most common side effect is involuntary movements of the body and this affects almost all patients who have suffered Parkinson’s disease a longer time. Duodopa® maintains a steady level of L-dopamine, which reduces the risk for these involuntary movements. Temporary dizziness may occur when standing up quickly from a laying down position, and is quite common among patients treated for Parkinson’s disease with L-dopa or dopamine agonists. It is advisable to remain in a sitting position on the edge of the bed for a while before standing up to minimize the risk of falling over because of a drop in blood pressure. Confusion or hallucinations, particularly during nights, may result from treatment with all antiparkinsonian agents and in such cases one may have to consider lowering the dose, or even discontinuing, one or a number of the medicines. More serious problems with hallucinations can be treated with special medicines called neuroleptics.
Question: Does Duodopa® produce any serious side effects?
Answer: No, Duodopa® is not known to produce any serious side effects.
Question: Who may need Duodopa®?
Answer: Duodopa® may be administered to individuals who experience the so-called complications phase in Parkinson’s disease, i.e. the stage in which medication is difficult to control and motor function is unstable. The patient must be able to respond to L-dopa therapy, i.e. show improved motor function. Usually the patients show serious motor-function fluctuations in spite of carefully adjusted treatment with tablets. The fluctuations range from severe rigidity and reduced mobility (off-periods) to intense involuntary movements of the body. The fluctuations are often rapid and sometimes difficult to anticipate in relation to tablet administration. The so-called on-period, i.e. the daily period of good mobility, is often very limited. Duodopa® treatment may offer an extended daily period of normal or near normal motor function in comparison with tablet treatment.
Question: Why is Duodopa® treatment available only to patients with advanced Parkinson’s disease?
Answer: The early stages in Parkinson’s disease, the “good years”, are adequately treated with tablets. At this stage, there is no need for a constant administration of the medicine for the purpose of achieving stable mobility. This is partly because patients are still able to store dopamine in their nerve cells for future needs.
Question: Is it possible to inject Duodopa® directly into the blood?
Answer: No, it is absolutely out of the question to administer Duodopa® directly into the blood! The gel is viscous and would block the blood vessels.
Question: Is it important to start and stop the treatment at fixed times?
Answer: No, the times do not need to be exact. The pump should be active when there is a need for movement, which in practice means that the pump is started on the morning and turned off at bedtime in the evening.
Question: Can Duodopa® even be used overnight?
Answer: There is very limited experience of round the clock treatment. In those cases where there are problems during the night and there is a need to take extra doses of L-dopa, then you may consider having the pump active even during night time.
Question: Are other antiparkinsonian agents useful in combination with Duodopa®?
Answer: Duodopa® is normally given as a monotherapy, i.e. there is no need to combine it with other antiparkinson medicines. Duodopa® in an L-dopa preparation and can be combined with other antiparkinson medicines but this does not typically lead an improved situation for the patient since the additional medicine can in fact cause an uneven stimulation of the dopamine receptors.
Question: Can Duodopa® be safely used in combination with other medicines?
Answer: There are no examples of Duodopa® combination therapy being dangerous. Duodopa® may however interact with other medicines, i.e. the therapeutic effect of any of the medicines involved may be affected. The following Swedish medicines can affect or be affected by L-dopa: Neuroleptics such as Buronil, Esucos®, Haldol®, Nozinan®, Risperdal®, Zyprexa®, ferrous iron medicines such as Duroferon®, Erco-Fer®, Niferex®, and tuberculosis medicines such as isoniazid. The antidepressive medicines Saroten®, Tryptizol®, and Tofranil® can cause high blood pressure in combination with L-dopa treatment. Combination therapy with selegilin and carbidopa/L-dopa has been associated with serious orthostatic hypotension (fall in blood pressure).
Question: How is Duodopa® affected by antibiotic treatment?
Answer: We have seen that in some cases it has been necessary to increase the dose of antibiotic treatment. It is not known if this due to that the medication is being affected or that the infection requires a larger dose.
Question: Is it possible to adjust the dose according to need?
Answer: Yes, generally speaking the dose should be adjusted based on need. In situations where movements deteriorate and remain so over the course of several days then of course the dose should be altered so that movement is normalized again. This is particularly common at the beginning of treatment since our brains are changeable and adapt according to different situations. The dose may even need to be adjusted over shorter periods, for example during an infection, although it should not be adjusted for transitory deterioration in movement caused by, for example occasional stress. Contact should be taken with your doctor/nurse when dose changes are made. In situations where motor function suddenly deteriorates and dose adjustment is difficult it is probable that the tube has moved back into the stomach. In such situations contact should be taken with a nurse or doctor who is familiar with the tubing system so that the tube position can be verified by X-ray and adjusted if necessary.
Question: Why does Duodopa® stain your clothes etc?
Answer: When exposed to aerial oxygen, L-dopa and carbidopa oxidize and become discolored. Carbidopa turns yellow and L-dopa turns black. If you spill it then it is important that you remove it immediately.
Question: Will Duodopa® make you totally symptom-free?
Answer: Some Duodopa® patients have become as good as entirely symptom-free after having experienced large fluctuations in mobility during treatment with tablets. It is important, however, to realize that this is not a cure from the disease and that significant motor-function fluctuations may still persist. The only thing absolutely certain is that the L-dopa concentration in the blood becomes significantly more stable from Duodopa® treatment than from treatment with tablets. The result is a more even production of dopamine in the brain. However, there are a number of mechanisms that present unsolved problems in this context such that motor-function fluctuations may appear in spite of a stable L-dopa concentration in blood. A common cause of unexpected motor-function problems is stress, for example in response to telephone calls, traveling, or an exciting film or sport on TV. Another reason is competition on the uptake and transport of L-dopa (see question “Can the meals you have interfere with the therapeutic effect of Duodopa®?”)
Question: Are there any long-term beneficial effects of Duodopa® treatment?
Answer: There is no definite scientific evidence to indicate that Duodopa® is slowing down the disease. However, after many years of therapy quite a few patients still have much more stable motor function compared with when they were treated with tablets, and this was without the need to increase the dose. This is in spite of Parkinson’s disease being progressive, i.e. the patient condition deteriorates slowly with time. Presently it is too early to conclude anything about the long-term effects; the number of patients is too limited for that. However, many scientists believe that an even stimulation of the dopamine receptors of the brain is beneficial.
Question: Can the meals you have interfere with the therapeutic effect of Duodopa®?
Answer: Since L-dopa is an amino acid, absorption into the blood and transport to the brain may be inhibited by the presence of similar amino acids in your food; this explains why food high in protein may reduce the therapeutic effect Duodopa®. Everybody does not experience the reduced effect but some patients do have considerable problems. It might be a good idea to take an extra dose before you start eating; this gives your brain the extra L-dopa that it may require later if protein in the food should compete with the medicine. Another suggestion is to have most of your high-protein food in the evening and eat low-protein food during the rest of the day. However, it is important not to reduce the total daily intake of proteins; your body requires the protein-derived amino acids.
