Generally, it’s best to keep it brief when you’re calling in sick, so don’t feel pressured to elaborate.
It might be in your company’s policy that you need to give some details about why you’re missing work. If that’s the case, just mention that you have stomach cramps or digestive issues. If your boss really presses for details, then it’s okay to mention that you have diarrhea to them.
Your boss will usually keep your symptoms a secret and just tell your coworkers you’re sick so you don’t get embarrassed.
This is especially true if you work in food service since you could potentially contaminate anything you serve to a customer. If you’re gone for an extended amount of time, your boss may ask for a doctor’s note for proof that you were sick.
If your symptoms are caused by allergies, then take over-the-counter allergy medication instead to relieve your symptoms and return to work.