Feeling shaky or experiencing tremors can be a concerning sensation. If you’ve ever asked yourself, “Why Do I Feel Shaky?”, you’re not alone. Occasional shakiness is often triggered by temporary factors like stress, fear, or even a fever. However, persistent or recurring episodes of feeling shaky warrant a closer look to understand the underlying causes. It’s crucial to remember that while feeling shaky can be a symptom of an underlying issue, in many cases, especially if you are otherwise healthy, it’s often due to benign conditions like essential tremor. Let’s delve into the common reasons why you might be experiencing these tremors.
What Exactly Are Tremors?
Tremors are characterized by involuntary, rhythmic shaking movements in one or more parts of your body. Think of your muscles working in pairs, opposing each other to control movement. When these opposing muscle groups contract and relax alternately, it results in a tremor. This movement is typically not under your conscious control and can manifest as a trembling or shaking feeling.
It’s important to note that everyone experiences a slight tremor known as physiological tremor. This subtle shaking is often unnoticeable. To observe it, try extending your hands straight out in front of you with fingers spread. Upon closer inspection, you might detect a very slight tremor, which is perfectly normal. Certain factors can amplify this physiological tremor, making it more noticeable at times.
How Common Are Tremors?
Tremors that are significant enough to prompt a visit to the doctor are surprisingly common. In fact, tremors are the most frequently encountered movement disorder in neurology specialist clinics within hospitals. Conditions such as essential tremor often have a genetic component and can run in families.
Your risk of developing tremors due to other underlying conditions varies depending on the specific condition. Let’s explore some of the common causes of tremors.
Unpacking the Causes of Tremors
Tremor itself is a symptom, not a disease. Sometimes, the cause remains unclear. In other instances, it’s an amplification of normal physiological tremor, triggered by temporary stimulants like caffeine or certain medications. Here are some of the most prevalent and significant causes of tremors:
Essential Tremor
Essential tremor stands out as the most frequent cause of persistent and noticeable tremors. It was previously termed ‘benign essential tremor’ because it was not considered harmful, life-threatening, or indicative of other conditions.
However, for many individuals, the uncontrollable shaking associated with essential tremor is far from benign. It can significantly hinder everyday tasks and profoundly impact self-esteem.
Anxiety and Stress
Anxiety, akin to excitement, triggers the release of adrenaline (epinephrine), the ‘fight or flight’ hormone. This hormone initiates widespread effects throughout the body, primarily aimed at enhancing alertness, muscle strength, and the ability to escape danger or confront it.
Adrenaline stimulates nerve endings, heightening awareness, and increases blood flow to arm and leg muscles. Both these responses can make you more prone to trembling.
Besides the evident feeling of anxiety, anxiety-related tremors are often accompanied by a rapid heartbeat (palpitations), shortness of breath, dry mouth, and sometimes chest discomfort.
Low Blood Sugar (Hypoglycemia)
Episodes of low blood sugar, or hypoglycemia, are most common in individuals with diabetes who are treated with insulin or sulfonylurea (SU) tablets for type 2 diabetes.
SU tablets stimulate the pancreas to produce more insulin, which can sometimes lead to excessively low blood sugar levels. Other symptoms of hypoglycemia include sweating, intense hunger, irritability, difficulty concentrating, nausea, blurred vision, and palpitations.
Caffeine Overconsumption
Similar to adrenaline, caffeine is a stimulant that increases alertness and nerve stimulation. While beneficial for staying awake, excessive caffeine intake in a short period can trigger tremors and palpitations.
Medication Side Effects
Certain medications are known to induce tremors as a side effect. These include excessive doses of salbutamol (used in asthma inhalers), lithium carbonate (typically prescribed for bipolar disorder), some anti-epileptic drugs, and certain cancer treatments. Some antidepressants can also cause shakiness, particularly when starting treatment.
Recreational Drug Use
Various recreational drugs, including MDMA and amphetamines, can cause tremors and other movement disorders. These issues may persist even after discontinuing drug use.
Alcohol Withdrawal
For individuals dependent on alcohol, withdrawal can lead to severe symptoms, including shaking, anxiety, confusion, sweating, palpitations, and even seizures. This tremor can persist for weeks after ceasing alcohol consumption.
If you suspect you are experiencing alcohol withdrawal, it’s crucial to seek immediate medical attention. Sudden cessation of alcohol is dangerous for those dependent on it. Gradual reduction over weeks, with support from alcohol services, is recommended.
Chronic alcohol use can also damage the brain, particularly the cerebellum, which is vital for balance and movement coordination. Individuals with alcohol dependence may experience frequent ‘mini-withdrawals’ within hours of their last drink, leading to recurring tremors.
Parkinson’s Disease
Tremor is one of the three hallmark symptoms of Parkinson’s disease, although it’s not always present. When tremor does occur in Parkinson’s, it typically affects the hands and arms and tends to be more pronounced when at rest.
Other primary symptoms of Parkinson’s disease—slow movement and stiffness—may emerge around the same time as tremors. However, they are sometimes mistakenly attributed to aging or lack of fitness. Consequently, tremor is often the initial symptom that prompts individuals to seek medical advice, frequently leading to a Parkinson’s diagnosis.
Overactive Thyroid Gland (Hyperthyroidism)
An overactive thyroid gland can cause shakiness along with other symptoms like unexplained weight loss despite increased appetite, anxiety, palpitations, sweating, heat intolerance, diarrhea, and shortness of breath. Initially, you might experience only one or two symptoms, with more developing over time.
Multiple Sclerosis (MS)
Tremor can be a symptom of multiple sclerosis, but it’s unlikely to be the sole symptom. Other causes of tremor are far more common in isolation. In MS, tremor typically appears as a later symptom, with an average of 11 years between MS diagnosis and tremor onset.
Vitamin and Mineral Deficiencies
Deficiencies in certain vitamins, especially B1, B6, and B12, can contribute to tremors. Similarly, Wilson’s disease, a rare inherited condition causing excessive copper accumulation in the body, can also cause tremors. Rarely, poisoning from arsenic or heavy metals can manifest with tremors among other symptoms.
Diagnosing the Cause of Tremors
Since tremor is a symptom, diagnosis focuses on identifying the underlying cause. Effective tremor treatment hinges on accurate diagnosis. Doctors often begin by asking targeted questions to narrow down potential causes, such as:
- Is the tremor present when you are resting? Rest tremors are typically linked to nervous system conditions like Parkinson’s disease or MS. In Parkinson’s, tremor often lessens with movement.
- Do tremors occur when holding a body part (usually an arm) against gravity? This type, which can also be triggered by movement, can be due to physiological tremor (exacerbated by overactive thyroid, anxiety, or high caffeine intake), certain medications, nervous system disorders, and chronic alcohol abuse.
- Does the tremor worsen when attempting to point at a specific object? Increased tremor intensity as you approach a target, known as intention tremor, may indicate a problem with the cerebellum.
- Which body parts are affected by tremor? Essential tremor and Parkinson’s tremor often start in one hand or arm.
- Is the tremor constant, or intermittent? If intermittent, what triggers it? (e.g., caffeine, stress).
- Are there other accompanying symptoms? Tremor is the first symptom reported by about 70% of Parkinson’s disease patients.
Doctors will physically examine the tremor and assess nerve function in your head, arms, and legs for other neurological signs. Sometimes, this examination is sufficient for diagnosis. Depending on the suspected cause, further tests may be necessary, such as blood tests to assess thyroid function or brain scans if Parkinson’s disease is suspected.
Tremor Treatment Options
Tremor treatment is highly dependent on the underlying cause. For instance, if an overactive thyroid is the culprit, correcting thyroid hormone levels should resolve the tremor. For anxiety-related tremors, talking therapies like cognitive behavioral therapy (CBT) may be recommended.
If medication is implicated, adjusting the dosage or switching medications may help, but this should only be done under medical supervision. For type 2 diabetes, alternative medications to sulfonylureas, which can cause hypoglycemia, are available. Discuss these options with your doctor.
Regardless of the tremor’s cause, excessive caffeine can worsen it. Consider reducing your intake of caffeine from sources like tea, coffee, cola, and chocolate, or eliminating it entirely. While alcohol might temporarily reduce tremor, excessive alcohol intake can lead to severe, debilitating tremors and other serious health complications. Therefore, doctors never advise using alcohol for self-medication.
Treatment options for essential tremor, the most common type of tremor, are detailed in a separate resource on Essential Tremor. These treatments are sometimes applied to other types of tremors, particularly if they significantly impact quality of life.
