It is not uncommon for some patients to have Parkinson’s symptoms but lack effective improvement and unsatisfactory efficacy on anti-Parkinsonian drugs. The reasons for this need to be analyzed specifically in order to develop a reasonable treatment strategy. There are four main reasons for this: 1. They actually work, but are considered ineffective by patients Some Parkinson’s patients have high expectations of efficacy and judge some initial improvements as “ineffective. Medical studies have shown that overall improvement of more than 30% in Parkinson’s patients is considered effective after taking the drug, while tremor-dominated patients may have an overall improvement of only 20% or more. This is common in patients with early PD, or in patients who are taking small doses of medication or are afraid to take strong medications such as methyldopa because of side effects. In this case, a standardized acute levodopa efficacy trial can be performed as a short-term hospitalization. 2. Inadequate dose The efficacy of Parkinson’s drugs is dose-related. If the dose of medication does not reach the effective “threshold”, the concentration of Parkinson’s drugs in the body does not cross the effective “threshold”, which may result in no efficacy despite taking medication. Therefore, if a patient takes 0.25 or 0.5 tablets of Methocarbamol, the effective dose can be increased if there is no effect; for patients in the middle and late stages, this effective dose may need to reach 0.75 or 1 tablet of Methocarbamol. For such cases, the drug dose can be increased within the safe range for a standardized acute levodopa efficacy trial. 3. Individual differences in patient drug response For the same class of drugs, different patients may have different efficacy responses. For example, most patients taking methyldopa are effective, but some patients taking methyldopa are ineffective after switching to benztropine. Some patients who were ineffective on Senfuro were effective when switched to Tysudar, although both drugs are dopamine agonists. In this case, the first step is to conduct the necessary examination to clarify the diagnosis, and then experimentally switch to similar drugs. 4. Lack of responsiveness of patients to drugs Some Parkinson’s patients have no clear efficacy regardless of which Parkinson’s drugs they take, even taking high doses of Methotrexate, and this performance suggests that the patient may have Parkinson’s syndrome rather than Parkinson’s disease. In this case, medications should not be adjusted blindly, and a series of specialized tests are first needed to identify the condition. For example, PET imaging of dopamine transporter protein should be used to check whether there are any lesions of the dopamine transporter system in the patient’s head; MRI of the head should be used to analyze whether there are any characteristic lesions of the brain, such as brain atrophy, hydrocephalus, hydrocephalus or even brain tumor; and other neurological system should also be checked for lesions.