Dog Articles

Cimetidine (Tagamet®), Ranitidine (Zantac®), and Famotidine (Pepcid®)


Cimetidine, ranitidine, and famotidine are related medicines.   They are in a class of drugs called H2 blockers.  They have similar effects and uses in veterinary medicine.

H2 blockers cause decreased production of stomach acid.   In pets, these medicines are prescribed mainly to treat or prevent gastrointestinal upset (vomiting, diarrhea, or lack of appetite).  They also may be used to prevent or treat ulcers or irritation of the esophagus, stomach, or intestines.

Fever of Unknown Origin in Cats and Dogs

Animals Affected

Cats and dogs


Fever of unknown origin is a common syndrome in cats and dogs.  Affected animals experience an elevated body temperature, usually accompanied by lethargy, weakness, and lack of appetite.

As the name implies, the cause of fever of unknown origin is not determined in most cases.  However, most pets with the syndrome are treated for bacterial infections.  This treatment usually is successful.

Ear Mites in Cats and Dogs

Animals Affected

Cats, dogs, puppies, and kittens.


Ear mites are parasitic organisms that infest pets.  They may cause intense irritation and itching in the ears, accompanied by production of large amounts of ear wax.

Ear mites are a leading cause of ear problems in kittens and cats.  They can infest dogs and puppies as well, but are a less frequent cause of problems in this species.

Doxycycline (Vibramycin®)


Doxycycline is an antibiotic related to tetracycline.   It is effective against a variety of organisms, and is often used to treat bacterial infections. It is the antibiotic of choice for many diseases (such as Lyme disease) that are spread by ticks and some diseases caused by organisms known as Mycoplasma.  It is commonly employed in the treatment of respiratory infections and fever of unknown origin in cats.