Hydrocodone Bitartrate

(for veterinary information only)


(tablets somewhat
difficult to obtain)


Narcotics are able to bring about many bodily effects beyond the notorious addictive euphoria. Other effects the medical profession has been interested in include: analgesia, anti-diarrheal effects, cardiovascular effects, and cough suppression. Hydrocodone represents a narcotic developed to accentuate the cough suppression effect. It is somewhat more effective in this regard than codeine (another famous narcotic with strong cough suppression effects). Cough suppression by narcotics is created by direct action on the cough centers of the brain.

Hydrocodone also tends to dry respiratory secretions, a desirable effect in benign minor infections (see below). This effect is further accentuated with the addition of a substance called homatropine; however, one of the chief reasons why homatropine is added to hydrocodone is to prevent abuse of its narcotic effects. Should someone attempt to consume more than a recommended dose of hydrocodone (and homatropine), some very unpleasant side effects of homatropine will prevent gross overconsumption.


Some typical situations in which cough suppression with hydrocodone would be helpful include:

  • Kennel cough (a usually minor infection leading to bronchitis).
  • Collapsing trachea (where the windpipe becomes flimsy).
  • "Old dog" bronchitis (a natural part of aging in dogs involves excess mucus production in the lungs).
  • Heart enlargement (where the right chambers of the heart become so large that as the heart beats they pinch off the main airways)

These are all conditions where minor secretions or actual tissues are pressing on the lung's airways and stimulating cough. Coughs that benefit from suppression are typically dry and hacking, often described as sounding as though something is stuck in the throat.

The effect of hydrocodone in a dog is believed to last approximately 6 to 12 hours. It is typically dosed at four times a day usage or less, as needed.


The chief side effects of hydrocodone use include:

  • Drowsiness or tranquilization
  • Drying of respiratory secretions
  • Constipation (if hydrocodone is given chronically)
  • Upset stomach

Notify your veterinarian if any of these side effects appear to be causing patient discomfort.


Serious side effects have been reported involving interactions between Anipryl/L-Deprenyl (treatment for "senility" in dogs as well as for in dogs) and Demerol (another narcotic). Based on this, the recommendation to avoid the use of Anipryl/L-deprenyl with any narcotics has been proposed; a different cough suppressant should be sought in such cases.

Mixing hydrocodone with other tranquilizers or with antihistamines increases the sedative side effects. (Note, there is a human product, brand name Tussionex®, which combines hydrocodone and chlorpheniramine which is an antihistamine. Clearly there are many human respiratory infections for which an antihistamine and cough suppressant combination might be bene ficial but the sedation effects will be increased.)


  • Cough suppression is not appropriate in the event of pneumonia. In pneumonia, there is excessive pus and mucus accumulation in the lung and this material must be coughed up. Suppressing the cough and drying the secretions will hinder the body's removal of this septic material.
  • Narcotic cough suppressants should be avoided in cases involving obstructive diarrheas or toxic diarrheas (such as canine parvovirus infection). The narcotic will improve the intestinal tone, which will assist in the absorption of water from the bowel and will improve stool consistency; however, it will also facilitate toxic absorption as well. In such situations, other forms of diarrhea treatment would be more appropriate.

Page last updated: 2/18/10