My 2-month-old boxer puppy has a swollen eye, rash, vomiting, and is tired.

Oh goodness! Poor Jack! As a veterinarian and fellow boxer owner I would expect that this is likely an allergic reaction to an insect sting or spider bite. Boxers are very reactive! They often have gastrointestinal signs with these reactions and usually take a few days to return to normal where as most dogs will respond within hours. He needs to be seen by a veterinarian immediately for some steroids and possibly even epinephrine. If his face is that swollen I worry that his throat could be swollen too, which could be very serious if it gets worse. Best of luck and I hope he improves soon. Thank you for using Pet Coach.

The eye must be checked immediately to make sure there is nothing wrong with it that requires immediate check up. A trauma, injury, acute inflammation/allergic reaction or infection could all be possible. Regarding the vomiting episode, I would recommend to withhold food for 12 hours and then start feeding her with a bland diet based in chicken and rice (boiled) in small portions every 6hours. Keep feeding her like that for 2days and then go back gradually to normal dietary regime.

I recommend getting your pet in to be seen by your veterinarian right away. Vomiting and lethargy together are very concerning and can lead to dehydration and electrolyte imbalance as well as low blood sugar. The swollen eye may or may not have anything to do with the vomiting. He could be having an allergic reaction. He might have eaten something that either disagreed with him or something that has gotten stuck somewhere in his gastrointestinal tract. He could be sore from a hidden injury you are unaware of, he could have been exposed to some sort of toxin or irritant in his environment or this could be early signs of another condition or disease process. Your pet may need IV fluids to help support his/her system and to be fasted at the same time in order to give the gut a rest. Your vet can do an exam, blood work and possibly x-rays to determine the cause of the illness and suggest an effective treatment plan.

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.

A droopy ear is usually not a sign of a neurologic problem - he could have an ear infection or sometimes the ear carriage will change as a puppy grows. The swelling around the eyes may have been a sign of an allergic reaction that could have resulted in vomiting. There are many other potential causes for vomiting as well ranging from ingesting non-food items to parasites to infections. If the vomiting continues or if his ear seems to be bothering him I'd recommend seeing your veterinarian.

Severe viral infection or congenital severe underlying heart disease could be responsible for the signs described. Ultrasound and ECG of the heart would be needed to confirm this clinical suspicion (of heart disease).

This is probably an allergic reaction due to an insect bite or a plant outside. those reactions tend to resolve within 48 hours without treatment. if the swelling, itchiness or vomiting do not resolve or if your dog is lethargic, take her to the vet in order to get an antihistamine injection.