Washing out remaining venom and pieces of spine will help minimize damage, speed healing and prevent infection. Leave an inaccessible spine alone only if it hasn't penetrated a joint, nerve or blood vessel. Seek appropriate medical care. Despite doing all of the above, some wounds will require surgical cleansing and repair, antibiotics for infection control, as well as antivenins and life support for severe stings. It is not always immediately obvious which stings will need more intensive medical care, so if at all possible, get care for all stings.
Some species eject a visceral liquid, causing dermatitis and blindness.
If eyes are involved, symptoms are similar to chemical burns. Copious irrigation of the affected area.