Cephalexin (brand names Rilexine®, Keflex®, Vetolexin®) is an oral antibiotic that is used to treat pyoderma and other bacterial skin infections in dogs and is used off label or extra-label in cats to treat pyoderma and some other types of skin infections. It is sometimes used off label or extra-label to treat urinary tract infections in cats and dogs. Side effects to cephalexin are usually mild and rarely occur. It may cause gastrointestinal upset including lack of appetite, vomiting, and diarrhea. Do not use cephalexin in pets that have a known hypersensitivity or allergy to cephalosporins.
Cetirizine (brand name Zyrtec®, Reactine®) is an antihistamine used to treat pruritus (itching) associated with atopic dermatitis, urticaria (hives), and insect-bite reactions in cats and dogs. Its use is in cats and dogs is ‘off label’ or ‘extra label’. Cetirizine does not typically cause any side effects. Vomiting and increased salivation has been observed in some dogs. Certain drugs are known to interact with cetirizine including central nervous system depressants (e.g., diazepam, alprazolam) and digoxin.
Chlorambucil is given by mouth and is used off label to treat certain types of cancer and autoimmune diseases. Common side effects include fur loss and changes in hair coat, as well as gastrointestinal upset. Do not use in pets that are allergic to it or other alkylating medications, that have bone marrow disease, have an active infection, or that are pregnant or lactating. If a negative reaction occurs, please call your veterinary office.
Chloramphenicol (brand names Chloromycetin® and Viceton®) is a broad-spectrum antibiotic used to treat many different bacterial infections, including those caused by anaerobic bacteria and Rickettsia. Chloramphenicol comes in tablet form, capsules, as a liquid suspension, and also in an injectable form (chloramphenicol sodium succinate). Exposure in humans can have severe consequences that are irreversible, so care must be taken to avoid accidental exposure.
Chlorothiazide/hydrochlorothiazide is given by mouth or injection and is used off label to treat nephrogenic diabetes insipidus, high blood pressure, fluid retention, and certain electrolyte imbalances. Give as directed by your veterinarian. Common side effects include electrolyte imbalances, increased need to urinate, vomiting, or diarrhea. Do not use in pets that are allergic to them or sulfa drugs, in lactating pets, or in pets that are not able to make urine. If a negative reaction occurs, please call your veterinary office.
Chlorpheniramine maleate is given by mouth and is used off label to treat allergic conditions or as a mild sedative. Common side effects include sleepiness, although other side effects are possible. Do not use in pets that are allergic to it or other similar antihistamines, or pets that are undergoing allergy testing within 2 weeks. If a negative reaction occurs, please call your veterinary office.
Chlorpromazine is given by mouth or injection and is used off label as a sedative and to treat vomiting. Common side effects include tiredness, low blood pressure, low heart rate, or a tendency to react or startle to noises. Chlorpromazine should not be used in pets that are allergic to it or in pets with low blood pressure. If a negative reaction occurs, please call your veterinary office.
Cimetidine is given by mouth and is used off label to treat various gastrointestinal conditions related to acid production, such as ulcers and reflux. Side effects are uncommon and have not been documented in animals. Do not use in pets that are allergic to it or other histamine2 blockers. If a negative reaction occurs, please call your veterinary office.
Ciprofloxacin ophthalmic (brand name Ciloxan®) an antibacterial agent used in the treatment of eye infections in dogs and cats. Its use in dogs and cats is off label or extra label. This medication should not be used in dogs that are allergic to quinolones. Some mediations may interact with ciprofloxacin, so it is important to tell your veterinarian about any medications that your pet is taking. If a negative reaction occurs, please call your veterinary office.
Ciprofloxacin is a systemic fluoroquinolone antibiotic used to treat bacterial infections. It is often given by mouth, but an injectable form is also available. The most common side effect is gastrointestinal distress, but other side effects are possible. It is contraindicated in young or dehydrated pets, or in pets with liver or kidney disease. It should not be the first-choice fluoroquinolone for veterinary patients.