10 Oct 2016
Jon Bowen discusses various ways to manage or desensitise canine and feline patients to common loud noises.
Jon Bowen
Job Title
Figure 1. Some of the interventions and treatment options available in the lead-up to Guy Fawkes Night. As the event approaches, each option becomes more constrained.
In a 2005 survey for the RSPCA, 49% of UK dogs were found to exhibit some degree of fear of firework, thunder or gunshot noises1.
However, it did not look at the severity of the fear problems reported, so we do not know what proportion of dogs were badly affected for the problem to have an impact on their health or quality of life.
As part of a series of studies to develop an online sound sensitivity questionnaire, the author et al characterised a number of aspects of noise fear in dogs2,3. They found the same overall proportion of dogs as the RSPCA study was afraid of loud noises, but about a third of those fearful dogs could be classified as severely affected. These were dogs that reacted to firework, thunder or gunshot noises distant and almost inaudible to their owners. They also showed high levels of distress during noise events.
After an incident, these dogs would take a long time to recover and often be nervous, even the day after a noise incident. This level of sound sensitivity makes it hard for dogs to enjoy a normal quality of life – they really need behavioural therapy and, in many cases, medication.
Evidence also exists to suggest problems of fear and anxiety may impact the health of animals. In one study, dogs with non-social fear and separation anxiety experienced significantly increased severity and frequency of skin disorders, and dogs with a fear of strangers had a significantly shorter lifespan4. The worst affected noise-sensitive dogs will eliminate or vomit during events, so it is quite likely these animals are at a high risk of stress-related health problems.
Typically, clinics experience a surge in demand for help with noise fears a fortnight prior to a public event, such as Guy Fawkes Night. Unfortunately, the range of interventions on offer becomes more constrained as the event approaches (Figure 1).
In many cases, behavioural therapy, such as desensitisation, can produce an improvement in eight weeks, but often takes much longer in severely affected dogs. Long-term medication will usually take four to eight weeks to produce an effect. Even short-term anxiolytic drugs, such as diazepam and alprazolam, should only be used after the effects have been tested on an individual dog.
It is also clear noise fears tend to get worse over time, with only 4% of the dogs in the RSPCA study spontaneously improving. So, early detection is important not only for treatment, but also to prevent the development of more serious problems.
The author and Jaume Fatjo developed a short online “sound sensitivity questionnaire”2,3, which has been translated into several languages, including French, German and Spanish. This can be completed in the clinic or clients can be sent a link so they can fill it in at home. This has the advantage that it is easy to contact a large number of clients very easily. The questionnaire has been made publicly available through sponsorship from Ceva Animal Health, and is available from www.ceva.co.uk
The questionnaire generates scores for several aspects of the dog’s reaction to noise events and indicates how severely it is affected. It also provides some basic advice on how to help the dog. A simple algorithm enables clinicians to determine the best level of treatment to offer (Figure 2).
Since the questionnaire has high retest reliability, it can also be used to determine whether the owner has made the correct changes necessary to enable the dog to cope better with noise events and track the improvement or deterioration of a case over time. This can identify whether therapy has been effective.
The incidence of firework fear has been found to be lower in UK dogs born in autumn1.
This is close to the start of the firework season in the UK, so puppies born at this time would be exposed to firework noises during their sensitive period. This is confirmed by the finding puppies that had experienced thunder during the first four months of life were 2.26 times less likely to develop a fear of thunder, compared with those that had not experienced it5.
This effect is not confined to exposure to real events; exposure to sound recordings of thunder and fireworks during the sensitive period (for example, at a puppy socialisation class) has been shown to reduce problem risk by five to seven times6. Some practical challenges exist when playing sounds to puppies to habituate them, not least of which is finding recordings of suitable quality.
Several years ago, the author and Sarah Heath made a product for habituating puppies to noises to a wide range of sounds, including fireworks and thunder, which is available to download from http://bit.ly/1iLMfTl
An instruction manual is included, which also contains information about socialisation and how to deal with a range of minor behavioural problems commonly seen in puppies. The author would recommend clinics publicise this resource to all clients who breed dogs.
The main methods for dealing with dogs that have noise fears include:
The choice of treatment depends on the severity of the dog’s reaction, as well as the frequency and intensity of sound exposure it experiences. Severely affected dogs will probably need the full spectrum of treatments, from short-term medication to long-term medication and therapy. Mildly or moderately affected dogs respond very well to desensitisation and counter-conditioning alone.
Typically, dogs prefer to hide in a dark, quiet place away from household activity, but they may also want to be close to a person for added security.
Making the following additions can help improve a hiding place:
A dog is more likely to use a hiding place if it likes to go there at other times. If possible, the hiding place should be set up a week ahead of any expected loud noise event.
Owners should give the dog treats and chews when it is in the hiding place, and show attention and approval when they find the dog there. This allows time for the dog to get used to the hiding place and associate it with pleasant experiences. This hiding place must be available to the dog at all times, regardless of whether the owner is at home.
Owners must not force animals to confront their fears by, for example, cutting off opportunities to hide. This can make dogs worse and, in some cases, lead to aggression. Comforting a fearful or phobic dog excessively should also be avoided, because it is possible to foster excessive dependence.
The best advice is to provide the dog with a secure hiding place it can go to at any time, as this has been found to reduce stress and fear. Often, dogs already go to a specific place to hide, such as a bathroom or behind a sofa, and the best option is to make this existing hiding place better.
Dogs that show a lot of freezing, low body posture and repeated unsuccessful attempts to hide (such as going from one hiding place to another or never fully settling) have not found a suitable place. The owners should be encouraged to provide a hiding place in accordance with the instructions in Panel 1.
Several studies have shown the benefit of desensitisation and counter-conditioning using recorded firework sounds.
After an eight-week plan of behavioural therapy using recorded sounds, dogs were tested with a different sound recording and the clients were asked to evaluate their dog’s response to real firework events7. Substantial and significant improvements were found after this brief intervention, and these benefits were found to persist, with severity scores remaining lower than at baseline after a year without further treatment8. Clients rated the procedure to be easy and worthwhile.
The therapy programme evaluated in these studies was Sounds Scary, which the author developed in conjunction with Sarah Heath, and was discussed previously.
Evidence suggests the effects of behavioural therapy last for at least 12 months after treatment, but it is generally recommended dogs should undergo occasional “top up” sessions to maintain their resilience to loud noises.
Medication can be used as a short-term strategy to enable a dog to deal with an inevitable event or circumstance, or as a long-term treatment that assists in the application of behavioural modification techniques over a period of weeks and months.
The favoured approach for short-term treatment is the use of benzodiazepine and triazolobenzodiazepine drugs. Until recently, the most frequently prescribed drug was diazepam, but in the UK this has largely been superseded by the triazolobenzodiazepine drug alprazolam.
Alprazolam has been shown to be an effective short-term anxiolytic in noise fears and phobias9. Given at a dose rate of 0.02mg/kg to 0.1mg/kg, alprazolam has a short half-life of approximately four to six hours and a wide therapeutic range. Unlike diazepam, ataxia and hyperexcitability are uncommon, but a test dose should always be administered to check a patient’s response before using the drug for a real event. A test dose of 0.02mg/kg should be given on a quiet day.
In animal models, alprazolam has been shown to have both retrograde and anterograde amnesic effects. The same effects have been reported in dogs receiving alprazolam for noise fear. To achieve an amnesic effect, alprazolam may be given at low dose (0.02mg/kg), before, during or after a fearful event. However, evidence and anecdotal experience exists the regular use of alprazolam alone during a season of noise exposure can reduce reaction to loud noises.
Due to its amnesic properties, alprazolam may also be used as a “safety net” after the completion of a long-term drug and behavioural therapy programme to prevent a relapse. It can be given after an intense noise event to block memories that might undermine therapy.
There is potential for these drugs to be abused and prescribing patterns should be monitored to ensure clients are not obtaining them for personal use.
Long-term drugs can improve the response to behavioural therapy, alleviate the debilitating effects of intense fear and improve the welfare of the animal. They can also limit progression of the problem, such as generalisation.
In general, they should be reserved for the treatment of dogs classified as severe using tools such as the sound sensitivity questionnaire. However, long-term medication is also valuable for dogs that react less severely, but are exposed to loud noises very frequently.
Clomipramine is a serotonin re-uptake inhibitor (SRI) drug licensed in the UK for the treatment of separation anxiety in dogs.
SRI drugs reduce anxiety and panic, which makes them suitable for the treatment of dogs with severe noise fear. The efficacy of clomipramine at its standard data sheet dose has been confirmed in an open label prospective study9.
The main serotonergic alternatives to clomipramine are fluoxetine and sertraline, but these drugs are not licensed for use in animals.
Typically, serotonergic drugs are prescribed for a period of six months, after which they are gradually withdrawn over a period of six or more weeks. Gradual withdrawal is generally recommended for SRI drugs to avoid relapse, rebound anxiety and discontinuation syndrome.
Selegiline is licensed in the UK for the treatment of behavioural problems with an emotional origin, including fear. It is a selective irreversible inhibitor of monoamine oxidase, the enzyme that metabolises dopamine and phenylethylamine.
However, it also has some effects on serotonin metabolism, through its effects on monoamine oxidase A. As a result, it must not be co-administered with tricyclic antidepressants, SRI or selective SRI drugs, and a washout period of 14 days must be allowed between selegiline and these drugs (and vice versa).
Clinical experience suggests selegiline is effective in the treatment of noise fears associated with behavioural inhibition and symptoms of social withdrawal; for example, dogs that hide and refuse to leave the house. Effects are usually seen within eight weeks, sometimes in less than a month. Like serotonergic drugs, selegiline is typically prescribed for six months.
Although we know plenty of cats choose to stay indoors during storms or fireworks, we don’t know whether they experience the kind of lasting and pervasive distress seen in dogs. It is possible to treat fearful cats using noise desensitisation, but this is not straightforward and generally requires expert help.
The best way to help cats is to keep them inside after dark, starting from a week before and throughout the firework season. Cats should be provided with access to food, water, a choice of comfortable resting sites and a toilet. Owners may not like the idea of temporarily giving a cat an indoor litter tray, but it is not optional.
Cats don’t derive security from human contact, and evidence exists many cats find handling mildly stressful, even if they don’t show it. So, it is best to leave cats alone and not to intervene when they are frightened. Above all, it is important owners don’t pick up or try to soothe frightened cats, because this can lead to aggression.
For cats that show distress during thunder and fireworks, pheromone products may be beneficial and installed 7 to 14 days before fireworks can increase a cat’s sense of security, if is located in a part of the house where the cat tends to spend a lot of time.
Fear of loud noises is the most common, and best understood, behavioural problem affecting pets in the UK. A range of effective treatments and tools exist that facilitate problem detection and assessment, some of which are free.
By detecting cases early, and offering the most appropriate treatments, vets can improve quality of life for dogs and cats, and prevent them from developing serious problems that can affect owners’ quality of life.
