Hypocellularity can be caused by a variety of reasons, and the recovery time depends on the type of disease, the individual’s constitution, the treatment and care, and other reasons, and cannot be generalized. The normal value of leukocytes is (4-10)×10^9/L. The causes of hypocellularity include hematologic disorders, infections, medications, allergies, poisoning, and genetic disorders. The recovery time of leukocytes varies from cause to cause. If the cause is an infection, the patient needs to take symptomatic treatment to reduce the infection and the white blood cells will gradually recover after stopping the medication, about a week. If the disease is caused by the blood system or other causes of hypocellularity, the patient may not recover within a short period of time and will need to take appropriate measures depending on the disease. Therefore, patients with hypocellularity need to go to the hospital in a timely manner to clarify the cause of the disease and then treat the symptoms. You should pay attention to rest, eat a light diet and avoid overexertion.