Steroids are medications used to treat various conditions, mainly by reducing inflammation and suppressing the immune system. Corticosteroids, like prednisone, are the most common type used medically, mimicking hormones produced by the adrenal glands. These are distinct from anabolic steroids, which are used for muscle building. Many people starting corticosteroid therapy experience involuntary, uncontrollable shaking, known as tremors. This article addresses this specific symptom and its biological causes.
Identifying Steroid-Induced Tremors
Therapeutic steroids, such as prednisone and dexamethasone, can cause a noticeable, drug-induced tremor. This side effect manifests as an enhancement of the body’s natural physiological tremor, typically described as fine and fast, ranging from four to twelve movements per second. The tremor most commonly affects the hands and arms, but may also appear in the head, voice, or eyelids.
This shaking becomes more pronounced during voluntary movement or when holding a posture, such as extending the arms. This is known as an action or postural tremor, distinguishing it from the resting tremor seen in Parkinson’s disease. The severity is related to the dosage and duration of corticosteroid treatment; higher doses or prolonged use increase the risk.
How Steroids Affect the Nervous System
Corticosteroids induce tremors by interacting with the central nervous system (CNS) and modulating the response to stress hormones. These drugs mimic cortisol, binding to glucocorticoid receptors distributed throughout the brain. This binding alters neurotransmission and neuronal excitability, affecting the delicate balance of signals.
A primary mechanism involves the adrenergic system, which manages the “fight or flight” response. Corticosteroids increase the sensitivity of \(\beta\)-adrenergic receptors to catecholamines, such as adrenaline (epinephrine) and noradrenaline. This heightened sensitivity causes the body to overreact to normal levels of these stimulating hormones.
The resulting overstimulation creates an exaggerated signal traveling through the nerves to the muscles, leading to an enhanced physiological tremor. The increased adrenergic activity amplifies this peripheral mechanical oscillation. Essentially, the steroid does not create a new tremor but rather turns up the volume on the small, inherent tremor that everyone experiences.
Corticosteroids in the CNS can also interfere with inhibitory neurotransmitters, such as GABA (gamma-aminobutyric acid). By reducing the dampening effect of these inhibitory signals, the steroids allow for increased neuronal excitability. This overall state of heightened nervous system activity contributes to the involuntary muscle contractions that manifest as shaking.
Managing Symptoms and Seeking Medical Advice
Individuals who develop uncontrollable shaking while on a steroid regimen must consult their prescribing physician before altering the medication schedule. Although the tremor is generally not life-threatening, medical guidance is necessary for safe management. The physician may recommend a dose reduction, often by 25 to 33 percent, or suggest an alternative dosing schedule to mitigate the side effect.
Lifestyle modifications can also help reduce the severity of the shaking. Since the tremor is an enhanced physiological tremor, avoiding stimulants is beneficial. Reducing or eliminating caffeine intake is a common non-medical strategy, as caffeine acts as a powerful stimulant. Stress management techniques are also helpful, since emotional stress is known to worsen involuntary shaking.
If the tremor remains problematic despite these adjustments, the physician may prescribe medication specifically to control the shaking. Beta-blockers, such as propranolol, are often the first-line treatment because they counteract the increased adrenergic sensitivity caused by the steroid. Seek immediate medical attention if the shaking is severe or accompanied by other serious symptoms. Warning signs include a rapid or irregular heart rate, confusion, or severe weakness, which require prompt medical evaluation for a potentially more serious underlying issue.