Found this online for what it is worth...I do find Low Dose Naltrexone helpful for me:

"Internal tremors are a recognized neurological symptom in some individuals with long COVID, described as involuntary shaking, vibrations, or buzzing sensations inside the body—often without visible movement. These tremors can affect the limbs or the entire body and may significantly disrupt daily functioning and quality of life.

Prevalence and severity: A Yale-led study published in The American Journal of Medicine found that 37% of 423 long COVID patients (158 participants) reported internal tremors or vibrations. Those experiencing this symptom tended to have more severe long COVID, with higher rates of neurological, cardiovascular, and gastrointestinal symptoms, as well as worse overall health and quality of life.

Demographics and comorbidities: The symptom was more commonly reported in women (81% of female participants vs. 70% of males). Patients with internal tremors also had higher rates of new-onset conditions, including mast cell disorders, anxiety, stress-related disorders, and neurological issues like seizures.

Treatment and management: While no targeted therapy is yet established, some patients report relief using low-dose naltrexone (LDN), which may help reduce inflammation and modulate immune response. However, more research, including randomized controlled trials, is needed to confirm its effectiveness.

Recognition and validation: Many patients previously felt dismissed due to the symptom's invisibility and lack of medical awareness. This research helps validate their experiences and underscores the need for greater clinical attention to neurological manifestations in long COVID. "