My boxer threw up weeds and is lethargic. When should I worry?
Throwing up can be caused by a food sensitivity, dietary indiscretion, intestinal parasites, an intestinal blockage, bacterial infection, viral infection, the weather, food change, stress, etc.
I would fast him for 24 hours and then put him on bland food for two days, such as boiled white rice and boiled white boneless chicken meat, fed in small quantities over several feeds and then transition back to regular food slowly over a few days. If this does not clear up the vomiting or if the vomiting increases, or if your dog stays lethargic, he needs to see a veterinarian for an exam as there may be something more serious such as an infection going on.
Updated on September 23rd, 2025