One point of view that needs to be updated is whether or not levodopa is toxic and whether or not it will accelerate the progression of the disease, and this is a question that people are very worried about. In the past, many doctors would say that levodopa was poisonous and would speed up the progress of the disease, and that it should not be taken if it could be avoided, and that it should be taken sparingly, and that it should be taken only when it had to be used. Since the doctors said so, the patients would also think so, including some health care products sellers would also say so: levodopa is toxic, do not eat, eat my health care agent or eat my ancestral secret recipe, no poison. In fact, through the clinical research of experts, it is found that the life expectancy of patients suffering from Parkinson’s disease without levodopa treatment is relatively short. But from the beginning with levodopa, the average survival of Parkinson’s patients from less than 10 years to now has increased to more than 20 years, and already and normal life expectancy has not much difference. There is also a lot of data showing that there is no difference in life expectancy between patients treated with levodopa early on and normal people. This data comes from a large trial that followed more than 900 patients for more than 20 years and found that the life expectancy of patients who started using levodopa late in life was reduced, while those who received the treatment early had a more normal life expectancy. This suggests that levodopa should be non-toxic. A 2006 evidence-based review by the American Academy of Neurology states that levodopa does not accelerate the disease process. However, there is a phenomenon that cannot be avoided is that after taking levodopa for a few years, it is true that some side effects will appear, some patients have a very short effect, some patients will have anisotropia, and some patients will have some mental disorders, such as: hallucinations, delusions, etc., but this is not because of the toxicity of levodopa, but because the disease itself continues to progress or the dosage of the drug has not been adjusted properly. Current research has found that the efficacy of levodopa is reduced mainly due to a few reasons: one is the patient’s own reasons, that is, the patient does not absorb the problem, some Parkinson’s patients’ gastrointestinal tract is not very good, delayed gastric emptying, which will lead to poor absorption, the efficacy of the treatment is not obvious, you can drink a large glass of water when taking the agent, because the levodopa is absorbed only to the intestine, if in the stomach is not absorbed. If not, you can also eat some enhancement of gastric power of the agent, so that many patients can get some improvement. Another problem is the time of taking the medicine, when taking levodopa preparation, it is necessary to take it 1 hour before meal or 1.5 hours after meal, because food can affect the absorption of the drug. Furthermore, it is related to the characteristics of the preparation itself, because the half-life of levodopa is relatively short, one and a half hours after eating, the blood concentration of the agent is very high, and after one and a half hours, the blood concentration of the agent becomes low. But in the early stage, why doesn’t this happen? Because in the early stage, we still have more neurons growing in the brain, so after this drug is taken in it can be stored by this neuron, and after it is stored, it will be released slowly according to your needs, and you can’t feel the short half-life of this preparation. But as the disease progresses, the neurons in the brain are getting fewer and fewer, and then the neurons in the brain can’t store the dopamine that you distribute in the brain, and it works entirely on the basis of the concentration in your blood, and when you have it in your blood, it moves a little bit, and when you don’t have it, it doesn’t have an effect anymore. So there is a loss of efficacy, which is caused by the progression of the disease itself, not by any toxic side effects of levodopa.