The causes of prolonged lying back pain include improper posture, lumbar muscle strain, lumbar spondylosis and so on. 1. Improper posture: If you lie down for a long time, it is easy to cause lumbar muscle spasm and trigger pain. The symptoms can be relieved by changing the posture such as lying on the side, or appropriate activities, generally without treatment. 2. Lumbar muscle strain: lying for a long time may cause lumbar muscle strain. It can be treated by physical therapy (e.g. electrotherapy, iontophoresis, massage, acupuncture, etc.), drugs (e.g. muscarinic succinylcholine, non-steroidal drugs such as diclofenac sodium extended-release tablets, etc.), and so on. 3. Lumbar spondylosis: If suffering from the underlying disease lumbar disc herniation, lumbar spinal stenosis and other diseases, the patient will also have the above symptoms. The treatment can take medication (such as ibuprofen extended-release tablets, etc.), traction, physical therapy, etc., and minimally invasive surgery if necessary. In addition, the above symptoms may also occur if the patient suffers from underlying diseases such as lumbar spine instability and gluteal epiphyseal nerve entrapment syndrome. If the above symptoms do not improve, the patient should consult a doctor to clarify the cause and give targeted treatment. The above medication should be applied under the guidance of a pharmacist or doctor, avoiding blind self-medication to avoid adverse reactions.