Symptoms of mononucleosis (mono) typically include:
- Extreme fatigue, often severe in the first 2 to 3 weeks
- Sore throat, which can be very painful and may be mistaken for strep throat; sometimes with white patches on the tonsils
- Fever, often up to about 103°F (39.4°C)
- Swollen lymph nodes, especially in the neck, armpits, and sometimes groin
- Swollen tonsils
- Headaches
- Muscle aches or stiffness
- Skin rash, which may appear especially if certain antibiotics like ampicillin or amoxicillin are taken
- Enlarged spleen and/or liver, which can cause belly pain or discomfort
- Loss of appetite and general malaise
Symptoms usually develop 4 to 6 weeks after infection and can last from a few weeks up to several months, with fatigue often lingering the longest
. Additional less common symptoms may include puffy eyes, nausea, severe headache, sensitivity to light, chest pain, and trouble breathing. Severe cases can rarely affect the liver, heart, or nervous system
. Treatment focuses on rest, hydration, and symptom relief with over-the- counter pain and fever medications (avoiding aspirin in children and teens)
