What causes nausea when lowering the head, and what should be done?

Generally, nausea when lowering the head may be caused by conditions such as orthostatic hypotension, stimulation of inner ear balance receptors, indigestion, lumbar disc herniation, or Ménière’s disease. Symptomatic management through general measures, medication, and other treatments is required. If discomfort occurs, it is recommended to seek medical attention promptly and receive appropriate treatment under a doctor's guidance. Specific analyses are as follows:

1. Orthostatic Hypotension

When lowering the head suddenly, the rapid change in body posture can temporarily prevent adequate blood supply to the brain. Especially after prolonged squatting or sitting, sudden head-lowering causes blood to pool in the lower part of the body, leading to transient cerebral ischemia, resulting in dizziness and nausea. It is recommended to enhance cardiovascular regulation through regular physical exercise such as walking or jogging. Postural changes should be performed slowly, avoiding sudden head-lowering or standing up.

2. Stimulation of Inner Ear Balance Receptors

The inner ear contains sensory organs responsible for balance perception, such as the semicircular canals and otolith organs. When head position changes dramatically—particularly during head-lowering movements—these receptors may become overstimulated, triggering reflexive nausea or vomiting. It is advised to sit or lie down in a quiet, comfortable place, close the eyes, and keep the head still to allow the balance receptors in the inner ear to gradually return to normal function.

3. Indigestion

This is mainly caused by overeating. A large amount of food entering the stomach leads to gastric congestion due to increased blood flow for digestion, which may reduce blood supply to the brain. This can result in symptoms such as nausea, vomiting, and abdominal bloating when bending the head forward. Treatment may include digestive aids such as Jianwei Xiaoshi Tablets, Simo Tang Oral Liquid, or Domperidone tablets, used under medical supervision.

4. Lumbar Disc Herniation

Prolonged head-down activities such as working or studying at a desk, using a computer for extended periods, or looking down at a mobile phone can cause straightening or reversal of the cervical spine’s natural curvature. This may compress blood vessels and nerves around the cervical spine. When the head is lowered, this compression worsens, reducing blood flow through the vertebral arteries and causing cerebral ischemia and hypoxia, leading to symptoms like dizziness and nausea. Medications such as Cobamamide Tablets, Mecobalamin Tablets, or Ibuprofen Sustained-Release Capsules may be used under a physician’s guidance.

5. Ménière’s Disease

Ménière’s disease is likely associated with endolymphatic hydrops (fluid buildup) in the inner ear. Head-lowering movements may exacerbate pressure changes within the inner ear, worsening the fluid accumulation and causing dysfunction of inner ear structures. Typical symptoms include recurrent vertigo, hearing loss, tinnitus, and a feeling of fullness in the ear, often accompanied by dizziness, nausea, and vomiting. Treatment may involve medications such as Mannitol Injection, Dexamethasone Tablets, or Ginkgo Biloba Extract Tablets, administered under medical supervision.

Patients should pay attention to their posture. Appropriate neck extension exercises are recommended. Avoid prolonged head-down positions and perform more head-raising activities to improve blood circulation in the neck area, aiding recovery. In daily life, dietary adjustments are important—consume more foods rich in protein, calcium, and other nutrients beneficial to overall health.