Stormy weather: Various drug interventions can help dogs better cope with storm and other noise phobias. (Eric Bean/Getty Images)

Last month, we defined noise phobias and looked at behavior medication tactics that can desensitize dogs to the offending noise—storms in particular. This month, we'll examine various drugs such as benzodiazepines, tricyclic antidepressants (TCAs) and selective serotonin-reuptake inhibitors (SSRIs) that can also help alleviate noise-induced anxiety.

Panicolytics

The most common and humane treatment for noise phobias involve drugs designed to reduce or terminate anxiety and panic. Most of the medications used are benzodiazepines, although medications that affect blood pressure (propranolol), heart rate (clonidine) and sleep cycles (melatonin) have also been suggested.

Benzodiazepines have one major drawback: They're controlled substances. In high dosages, especially for the drugs with longer half-lives, benzodiazepines can induce physiologic dependence, which means they should not be introduced into households with human substance-abuse problems. But if used rationally in a dog that has had a complete physiologic and laboratory evaluation that showed no abnormalities, the benefits of this drug class can be great and the risks few.

The list of medications commonly used to treat storm and noise phobias focuses primarily on benzodiazepines given orally:

• Diazepam (0.5 to 2 mg/kg as needed)
• Clorazepate (0.5 to 2 mg/kg as needed; use about 11.25 mg for a medium-sized dog; sustained-release forms are sometimes available)
• Alprazolam (0.01 to 0.1 mg/kg as needed; best average dose is 0.02 to 0.04 mg/kg every four to six hours, as needed).

These medications are listed in order of duration—from longer- to shorter-action—of the parent compound. That said, no one wants a sedated or uncoordinated dog, and some of these medications (e.g., diazepam, clorazepate) are more likely to sedate dogs than are others (e.g., alprazolam).

Although diazepam and clorazepate have been commonly used to treat noise reactivity, the medication of choice in most dogs is alprazolam, in part because it does not use the N-desmethyldiazepam metabolic pathway. Any medication with N-desmethyldiazepam in its metabolic path can be sedating—an effect that's not desirable if using a medication frequently and hoping to avoid physiologic tolerance.

Alprazolam is not metabolized into N-desmethyldiazepam, so when it is given appropriately, it should not sedate the dog. The optimal dose of alprazolam for most dogs that have any element of panic to their response is 0.02 to 0.04 mg/kg. Because alprazolam comes in 0.25-, 0.5-, 1- and 2-mg tablets that are scored, it's easy to find a dose that works for most animals. For a medium-sized dog, starting with an initial 0.25-mg dose is best. As needed is generally interpreted to be every four to six hours, the approximate half-life of many benzodiazepines.

Alprazolam can be used as a preventive and as a panicolytic medication. To use it for prevention, the client must anticipate when there will be a provocative stimulus. Weather reports and Doppler radar can help. One choice for a medium-sized dog would be to give a 0.25-mg tablet one-and-a-half to two hours before the anticipated storm. Then repeat a full (0.25 mg in this example) or half dose 30 minutes before the event. Repeat every four to six hours as needed using either the half or full dose. Start with the half dose, as this dosing is cumulative.

To use alprazolam as a panicolytic, a full dose should be given immediately. If the dog is still distressed after 30 minutes, repeat with a half or whole dose. One of the terrific things about administering benzodiazepines is that they can be dissolved in a tiny amount of liquid or in a dog's cheeks.