Shaking, or tremors, can result from alcohol consumption due to various physiological responses. These tremors can appear acutely while alcohol is in the system, during a hangover, or as a more serious symptom of alcohol withdrawal. Understanding how alcohol affects the nervous system clarifies why these shakes occur.
How Alcohol Affects the Nervous System
Alcohol acts as a central nervous system depressant. It achieves this by enhancing the effects of gamma-aminobutyric acid (GABA), a neurotransmitter that reduces nerve excitability, and by inhibiting glutamate, an excitatory neurotransmitter. This dual action leads to sedative effects like relaxation and impaired coordination.
As alcohol is metabolized and leaves the system, the brain can experience a rebound effect. The nervous system, having adapted to the presence of a depressant, becomes overactive. This hyperexcitability can result in acute tremors or general shakiness, often accompanied by anxiety and agitation.
Shakes from Alcohol Withdrawal
Chronic alcohol consumption leads to adaptations in the brain’s chemistry. The brain attempts to counteract alcohol’s depressive effects by increasing excitatory neurotransmitter activity and decreasing inhibitory sensitivity. This creates an altered balance within the nervous system.
When alcohol intake is suddenly reduced or stopped after prolonged heavy use, the brain remains in this heightened, overexcited state. This imbalance triggers alcohol withdrawal syndrome, with tremors as a prominent symptom. These withdrawal shakes typically begin within 6 to 24 hours after the last drink, peaking around 24 to 72 hours. They can range from mild hand tremors to more generalized body shaking, often accompanied by anxiety, agitation, sweating, and an increased heart rate.
Understanding Delirium Tremens
Delirium Tremens (DTs) is a severe, life-threatening form of alcohol withdrawal. This condition is characterized by confusion, disorientation, and often visual, auditory, or tactile hallucinations. DTs also involve autonomic instability, presenting with severe tremors, rapid heartbeat, elevated blood pressure, and fever.
The onset of DTs typically occurs later in the withdrawal timeline, usually between 48 to 72 hours after the last drink, though it can sometimes appear up to 10 days later. It is considered a medical emergency due to the risk of serious complications, including seizures, irregular heart rhythms, and death if left untreated.
Other Causes and Complicating Factors
Chronic alcohol use can also contribute to tremors beyond acute intoxication or withdrawal. Long-term heavy drinking can lead to nerve damage, known as alcoholic neuropathy, which can cause tremors. Additionally, liver damage, such as alcoholic hepatitis or cirrhosis, can impair the liver’s ability to filter toxins from the blood.
Accumulated toxins can affect brain function, leading to a neurological complication called hepatic encephalopathy. A characteristic tremor associated with this condition is asterixis, often described as a “flapping” tremor of the hands. Alcohol can also exacerbate pre-existing tremor disorders, such as essential tremor or Parkinson’s disease, or interact with certain medications, worsening existing shakes.
When to Seek Medical Attention
Seek medical help if you or someone you know experiences shakes related to alcohol, especially if symptoms are severe or worsening. Any signs of confusion, disorientation, or hallucinations require immediate medical evaluation.
Other warning signs that require urgent medical attention include seizures, a rapid heart rate, chest pain, or a high fever. Alcohol withdrawal can be dangerous, and medical supervision is often necessary to manage symptoms safely and prevent life-threatening complications.