The muscle aches and joint pain that typically accompany a bout of mononucleosis are a product of the Epstein-Barr virus, which causes the disease, attacking the peripheral nervous system, explains the National Institute of Neurological Disorders and Stroke. Diseases of the peripheral nervous system are referred to as peripheral neuropathies.
The primary cause of mononucleosis, often shortened to mono, is the Epstein-Barr virus, a member of the herpes virus family, notes the Centers for Disease Control and Prevention. The microbe, also known as human herpesvirus 4, is typically spread through bodily fluids, primarily saliva, and to a lesser extent, through semen and blood. Some symptoms of an infection caused by the virus include a swollen liver, enlarged spleen and inflamed throat. The virus also attacks nerve tissue and causes symptoms such as muscle weakness, notes the National Institute of Neurological Disorders and Stroke.
Apart from muscle aches and joint pain, other symptoms of mono include drowsiness, sore throat, fever and muscle stiffness, notes MedlinePlus. Other symptoms include rashes, muscle stiffness, general discomfort, loss of appetite and swollen lymph nodes, typically those in the armpits and neck. Some of the more serious symptoms include sensitivity to light, headaches, chest pain, coughing, hives, an elevated heart rate, jaundice, nose bleeds and stiffness of the neck. Symptom relief is the typical goal of treatment, and patients are encouraged to take plenty of fluids, rest and avoid contact sports in cases in which the spleen is swollen. Medication such as ibuprofen may be prescribed to treat and pain and fever.