General:
* Shouting
* Screaming
* Yelling
* Calling out
* Exclaiming
* Vociferating
* Bellowing
Expressing distress or pain:
* Wailing
* Moaning
* Groaning
* Sobbing
* Weeping
* Lamenting
Expressing anger or frustration:
* Ranting
* Raving
* Protesting
* Complaining
Calling for help or attention:
* Appealing
* Pleading
* Begging
* Imploring
Other:
* Proclaiming
* Declaring
* Announcing
The best synonym will depend on the specific situation and the tone you wish to convey.