| Signs & Symptoms | Allergies | Cold | Flu |
|---|---|---|---|
| Onset | Sudden or gradual | Gradual | Sudden |
| Fever or chills | No | Mild, if at all | Moderate – high |
| Cough | Sometimes | Common, may produce sputum | Common (dry) |
| Chest Discomfort | No | Mild, if any | Sometimes |
| Sneezing and/or stuffy nose | Common | Common | Rare |
| Runny nose | Common | Common | Sometimes |
| Sinus pressure | Common | Sometimes | Rare |
| Stuffy ears | Sometimes | Sometimes | Rare |
| Skin rashes or hives | Sometimes | No | No |
| Red, swollen, or itchy eyes | Common | Watery eyes | No |
| Headache | Sometimes | Rare | Common |
| Sore throat | May be scratchy | Common | Common |
| Muscle/Body aches | No | Rare | Common – Severe |
| Fatigue | Sometimes | Mild | Common – up to two weeks |
| Weakness | No | Mild | Common |
| Duration | Varies | 7 – 14 days | 24 hours – 2 weeks |
| Nasal discharge | Clear | Yellow, clear or green | Rare |
| Voice loss | No | Sometimes | Sometimes |