Calling in sick without a doctor's note can feel a bit tricky, but it's common in many workplaces. While employers may request a note, not all situations require one. Some valid reasons could include flu-like symptoms where you feel feverish, have a bad headache, or are suffering from gastrointestinal issues like nausea or diarrhea. For those with migraines, these debilitating headaches can be unpredictable, and explaining that you cannot function properly at work can be enough. Mental health is just as important as physical health, so if you're feeling particularly stressed or anxious, that can be another valid reason. Though these excuses are valid, you should always be upfront and honest with your employer to maintain trust. Overuse of sick days without a doctor's note can lead to complications with your job or even losing credibility over time. Balance is key—if you use these valid excuses responsibly, you can keep a healthy relationship with your work while taking care of yourself.