What Causes Itchy Skin at Night?
Aug 18, 2021
Source: Cainiu Health
Dr. Li Ruizhi
Introduction
1. Hepatobiliary diseases: Itching of the skin at night is often associated with certain medical conditions; hepatobiliary disorders are a common cause of nocturnal pruritus.
2. Environmental factors: During winter, low ambient humidity causes the body to reduce heat loss by partially constricting cutaneous capillaries.
3. Endocrine disorders: For example, in hyperthyroidism, increased cutaneous blood flow may lead to pruritus.
Generally, the onset of skin itching before bedtime may be attributed to endocrine disorders. Moreover, hyperthyroidism—particularly when exacerbated in the evening—can elevate skin temperature, thereby triggering pruritus. Additionally, underlying conditions such as diabetes or liver disease, as well as environmental factors like temperature fluctuations, may also contribute to nocturnal itching. So, what causes skin itching specifically at night? Below, we address this question.
Causes of Nocturnal Skin Itching
1. Hepatobiliary Disorders
Nocturnal pruritus is often associated with certain medical conditions, among which hepatobiliary diseases are a common cause. Furthermore, pruritus may arise as a complication of other disorders—including atopic dermatitis (eczema), urticaria, diabetes mellitus, and renal disease—manifesting with varying degrees and frequencies of itchiness. Symptoms frequently worsen during winter months. If itching becomes severe enough to impair daily functioning, medical consultation is advisable.
2. Environmental Factors
During winter, low ambient humidity leads the body to reduce heat loss by partially constricting cutaneous capillaries, thereby decreasing cutaneous blood flow and reducing sweat and sebum secretion. This results in diminished skin hydration and dryness, which predisposes individuals to pruritus. Moreover, cold weather prompts many people to take hot showers—sometimes two or three times daily—which further depletes already scarce sebum, exacerbating skin dryness and increasing susceptibility to itching.
3. Endocrine Imbalance
In patients with hyperthyroidism, accelerated cutaneous circulation elevates skin temperature, provoking pruritus—often intensifying after falling asleep. Similarly, elevated serum calcium or phosphorus levels may induce itching. If accompanied by dry skin plus symptoms such as polyuria, urgency, flank pain, watery urine, or oliguria, renal disease should be considered.
The above outlines potential causes of nocturnal skin itching. We hope this information proves helpful.
