Shaking can be a concerning symptom for individuals navigating a cancer diagnosis and its associated treatments. Understanding the various potential causes can help patients and caregivers approach the symptom with more information. Shaking, often manifesting as tremors or involuntary muscle movements, can stem from the cancer itself, be a side effect of therapies, or arise from other physical and psychological factors.
Shaking Directly Linked to Cancer
The presence of a tumor can directly influence the nervous system, leading to involuntary movements. Tumors located in specific areas of the brain, such as the cerebellum or basal ganglia, can cause tremors and other movement disorders. Spinal cord tumors, as they grow and compress nerves or the spinal cord, can also result in muscle weakness, twitches, or spasms in affected areas of the body.
In some instances, shaking can be a manifestation of paraneoplastic syndromes. These rare conditions occur when the immune system, in its fight against cancer, mistakenly attacks healthy cells in the nervous system. This unintended immune response can lead to various neurological symptoms, including tremors, even when the tumor is not directly in the brain or spinal cord. Additionally, advanced cancer can lead to cachexia, a condition characterized by significant weight loss and muscle wasting. This physical decline and muscle weakness can contribute to overall body trembling or a feeling of instability.
Treatment-Induced Shaking
Cancer therapies themselves can induce shaking as a side effect. Chemotherapy agents are a common cause, particularly those that lead to peripheral neuropathy, a type of nerve damage. Drugs like taxanes (e.g., paclitaxel) and platinum-based agents (e.g., oxaliplatin, cisplatin) are known to cause neurotoxicity, which can manifest as tingling, numbness, or tremors. Vinca alkaloids, such as vincristine, can also cause peripheral neuropathy that impacts fine motor control and can lead to tremors.
Radiation therapy, especially when directed at the brain, can also result in neurological side effects. Radiation can cause inflammation or damage to brain tissue, potentially leading to symptoms like headaches, seizures, and in some cases, tremors. Beyond primary cancer treatments, other medications frequently used in cancer care may contribute to shaking. Corticosteroids, commonly prescribed to manage inflammation or nausea, and certain anti-nausea drugs like metoclopramide, can have tremors or other movement disorders as a side effect.
Other Contributing Factors
Beyond cancer and its treatments, several other medical conditions and physiological responses common in cancer patients can cause shaking. Infections are a frequent culprit, as the body’s response to pathogens often includes fever and chills. These “shaking chills” or rigors are intense, involuntary muscle contractions that accompany a rising body temperature, and they are particularly common in immunocompromised cancer patients.
Electrolyte imbalances, such as abnormal levels of sodium, potassium, magnesium, or calcium, can disrupt normal nerve and muscle function. These imbalances, caused by factors like treatment side effects, dehydration, or kidney issues, may lead to symptoms like muscle spasms, weakness, twitching, or tremors. Hypoglycemia, or low blood sugar, is another factor that can cause shakiness. This can occur due to inadequate nutrition, altered metabolism, or certain medications, and it often presents with symptoms like confusion, irritability, and a rapid heartbeat.
Psychological and physical stressors also play a role in the experience of shaking. High levels of anxiety, stress, or uncontrolled pain can manifest as physical trembling or tremors. The emotional challenges of cancer diagnosis and treatment can induce physical symptoms like shaking hands or overall body tremors.
Addressing Shaking and When to Seek Help
If a cancer patient experiences shaking, informing the healthcare team is an important first step. Open communication allows medical professionals to investigate the cause and determine the appropriate course of action. They may conduct blood tests to check for infections or electrolyte imbalances, or imaging studies to assess for neurological involvement.
Certain signs warrant immediate medical attention. These include sudden onset of severe shaking, shaking accompanied by confusion, significant weakness, or a fever of 100.4°F (38°C) or higher. These symptoms could indicate a serious underlying issue requiring prompt evaluation. While awaiting medical assessment, supportive measures can help manage discomfort. Maintaining adequate hydration, managing pain effectively, and employing stress reduction techniques such as deep breathing or relaxation can provide some relief. Ensuring sufficient nutrition can also support overall physical well-being.