Epidemiology

A specific phobia of vomiting (SPOV) has been a neglected area of research. Epidemiological studies suggest that the prevalence of specific phobias in general is extremely common with a 12-month prevalence of about 7–13% (Boyd et al. Reference Boyd, Rae, Thompson, Burns, Bourdon, Locke and Regier1990; Kessler et al. Reference Kessler, Chiu, Demler and Walters2005; Becker et al. Reference Becker, Rinck, Türke, Kause, Goodwin, Neumer and Margraf2007; Stinson et al. Reference Stinson, Dawson, Chou, Smith, Goldstein, Ruan and Grant2007). Of these, only one study specifically enquired about a phobia of vomiting which had a prevalence of 0.1% (Becker et al. Reference Becker, Rinck, Türke, Kause, Goodwin, Neumer and Margraf2007). The study by Stinson et al. (Reference Stinson, Dawson, Chou, Smith, Goldstein, Ruan and Grant2007) found the numbers of SPOV too small to analyse (Grant, personal communication in Stinson et al. Reference Stinson, Dawson, Chou, Smith, Goldstein, Ruan and Grant2007). These estimates are in sharp contrast to the estimates suggested by Kirkpatrick & Berg (Reference Kirkpatrick and Berg1981, cited in Philips, Reference Philips1985) and van Hout & Bouman (unpublished observations cited in van Overveld et al. Reference van Overveld, De Jong, Peters, Van Hout and Bouman2008) who claim a prevalence of 1.7–3.1% for males and 6–7% for females. However, these studies are based on a fear of vomiting rather than diagnostic criteria for SPOV.

There is significant overlap in SPOV especially with health anxiety and obsessive–compulsive disorder, for which it may have been misdiagnosed in some of the surveys. Despite being uncommon, clinicians generally regard SPOV as more difficult to treat and different in psychopathology compared to other specific phobias. For example, people with SPOV tend to be more handicapped than people with other specific phobias (e.g. avoidance of a desired pregnancy or being significantly underweight from restriction of food; Manassis & Kalman, Reference Manassis and Kalman1990).

Characteristics of SPOV

Lipsitz et al. (Reference Lipsitz, Fyer, Paterniti and Klein2001) and Veale & Lambrou (Reference Veale and Lambrou2006) have published surveys of people with a SPOV from internet support groups. These studies suggest it commonly develops in childhood with a mean duration of about 25 years and occurs almost exclusively in women (for this reason I will refer to clients in the female gender). The gender differences may be reflected in the normal population – men may be more likely to view vomiting as a joke and even desire to vomit after heavy drinking. Most people with a SPOV are predominantly fearful of their self-vomiting (Veale & Lambrou, Reference Veale and Lambrou2006). They may also strenuously try to avoid people who they believe to be at risk of vomiting usually because they believe it would put themselves at risk of vomiting. Even if there is no evidence that a person vomiting is contagious, such individuals are a stimulus for having to think about vomiting or feeling nauseous and a client may then believe that it would cause her to vomit by a process of magical thinking. A minority of people with SPOV are either exclusively or predominantly fearful of others vomiting (usually on them), as described by McKenzie (Reference McKenzie1994) and McFadyen & Wyness (Reference McFadyen and Wyness1983). This might be described as a subtype of SPOV or a different specific phobia. These people may be easier to treat and should be investigated separately in any controlled trial. The rest of this article therefore assumes that a client is predominantly fearful of herself vomiting (or of herself and others equally).

Davidson et al. (Reference Davidson, Boyle and Lauchlan2008) have highlighted the relationship between a heightened internal locus of control and a SPOV. This is in keeping with the experience of people with SPOV who fear losing control and who may convince themselves that they can avoid vomiting by controlling a reflex response. Van Overveld et al. (Reference van Overveld, De Jong, Peters, Van Hout and Bouman2008) found that people with SPOV have increased levels of disgust propensity and sensitivity and that this is the best predictor of symptoms in SPOV. Boschen (Reference Boschen2007) discussed a cognitive behavioural model and research agenda. He described how people with SPOV may be more vulnerable to general anxiety and somatization (a tendency to express anxiety through somatic symptoms – specifically gastrointestinal symptoms, e.g. nausea, bloating, diarrhoea, ‘butterflies’). They may have suffered aversive experiences of themselves and others vomiting.

In extreme anxiety, some people (especially children) may vomit probably through the parasympathetic vagal pathway which can also lead to immobility, fainting, dissociation and defecation (Porges, Reference Porges2007). The experience of vomiting as a child might be associated with the feeling of suffocation or death and be a factor in the development of SPOV. Ohman & Mineka (Reference Ohman and Mineka2001) suggest that a fear module is preferentially activated in aversive contexts by stimuli that are fear relevant in an evolutionary perspective. This can include food aversions that have developed after vomiting and could lead to avoidance of cues related to vomiting (Garcia et al. Reference Garcia, Rusiniak, Brett, David and Hurwitz1977). Such aversions are extremely enduring and this is a probable factor in the development of a SPOV. Ohman & Mineka (Reference Ohman and Mineka2001) also suggest that activation to such stimuli is automatic and is relatively impenetrable to cognitive control. They suggest that a fear module mediates an emotional level of fear learning that is relatively independent and dissociable from cognitive learning of stimulus relationships.

Diagnosis

A SPOV is relatively easy to diagnose when a client presents with a fear of vomiting. The key criteria for a specific phobia in DSM-IV (APA, 2000) are given in Table 1. The words in italics about vomiting have been added to the relevant criteria. DSM-IV classifies SPOV as Specific Phobia ‘Other type’ which may have the unintended effect of minimizing research into SPOV (Boschen, Reference Boschen2007).

Table 1. Key criteria for specific phobia of vomiting

I first discuss the differential diagnosis of SPOV from other anxiety disorders and anorexia nervosa and how they may be comorbid. It is particularly important to note the onset of a comorbid diagnosis and its functional relationship to SPOV.

Treating SPOV

A meta-analysis of controlled trials on treating specific phobias found in-vivo exposure to have the most evidence (Wolitzky-Taylor et al. Reference Wolitzky-Taylor, Horowitz, Powers and Telch2008). However the meta-analysis did not include specific phobias of vomiting and there are only six published case reports of SPOV treated by behaviour therapy or cognitive behaviour therapy (McFadyen & Wyness, Reference McFadyen and Wyness1983; Lesage & Lamontagne, Reference Lesage and Lamontagne1985; Philips, Reference Philips1985; Herman et al. Reference Herman, Rozensky and Mineka1993; Lesage & Lamontagne, Reference Lesage and Lamontagne1985; Hunter & Anthony, Reference Hunter and Antony2009); one of imaginal coping (Moran & O'Brien, Reference Moran and O'Brien2005); one of systemic behaviour therapy (O'Connor, Reference O'Connor1983); one of psychotherapy (Manassis & Kalman, Reference Manassis and Kalman1990); two of hypnotherapy (Ritow, Reference Ritow1979; McKenzie, Reference McKenzie1994) and one with a combination of the above (Wijesinghe, Reference Wijesinghe1974). There is likely to be a publication bias of successful cases and of those published, four are atypical: two predominantly fearful of others vomiting (McKenzie, Reference McKenzie1994; McFadyen & Wyness, Reference McFadyen and Wyness1983) and two of atypical social phobia (Lesage & Lamontagne, Reference Lesage and Lamontagne1985; McNally, Reference McNally and Davey1997).

This article describes a cognitive behavioural formulation, which incorporates many of the findings from a previous survey (Veale & Lambrou, Reference Veale and Lambrou2006), the paper by Boschen (Reference Boschen2007), as well as advances made in the treatment of anxiety disorders over the past 10 years.

Treatment model

The model used is of aversive memories of vomiting becoming associated with fear. Past aversive experiences of oneself or others vomiting (and their cues) become fused with the present so that they are re-experienced as if they are about to be repeated. It is possible that vicarious learning may also occur. Once the association is learnt, the core appraisal is of nausea as impending vomit (Clark, Reference Clark, Rachman and Maser1988) and the evaluation of vomiting as one of extreme awfulness leading to further anxiety and nausea.

There are various responses to a current threat of impending vomit.

1. (a) Experiential avoidance of thoughts and images of oneself or others vomiting and interoceptive cues for nausea.

2. (b) Avoidance of external threats that could lead to vomiting or nausea.

3. (c) Hyper-vigilance for monitoring external threats (e.g. people who could be ill or an escape route).

4. (d) Self-focused attention for monitoring of nausea.

5. (e) Worry, self-reassurance and mental planning of escape routes from others vomiting.

6. (f) An over-inflated sense of responsibility and belief in one's ability to stop oneself from vomiting.

7. (g) Safety-seeking behaviours including compulsive checking and reassurance seeking.

In a functional analysis, all these responses will have an unintended consequence of increasing the frequency of thoughts about vomiting and symptoms of nausea and will prevent disconfirmation of the threat of vomiting. Avoidance of people and activities related to vomiting prevents extinction and prevents disconfirmation of expectations and the ‘awfulness’ of a fear and reinforces avoidance of nausea and cues related to vomiting. Vomiting may occur rarely but it does not lead to a diminished fear response, perhaps because it does not occur frequently enough and the association with fear is very powerful.

Developmental formulation

The therapist should take a chronological history of the client's experiences of vomiting from the earliest age she can recall. This should include a past history of (a) when she vomited, (b) when she experienced panic or severe anxiety and strongly believed she was going to vomit, (c) when she witnessed others vomiting or was vomited upon. The therapist should also determine the age and the context in which the event occurred (e.g. an infection), and ask about how anxiety-provoking each experience was (e.g. on a scale between 0 and 10).

Imagery is a powerful means of evoking emotion and may be helpful to understand the associations or meaning attached to such experiences. If the client is willing (as this is a form of exposure in imagination), the therapist can ask her to close her eyes and re-experience the most distressing experiences in her mind's eye and to describe this in the first-person present tense from a field perspective (i.e. not looking back as an observer of oneself). Do any of these experiences of vomiting seem relevant to her current problem? Are there any relevant antecedents to vomiting – e.g. physical or sexual abuse? What aspect of the vomiting is totally unbearable? What happened after these experiences? For example, was a relative very critical of her vomiting? (For some, parental or peer attitudes to vomiting is relevant. For example, a woman with a SPOV may have learned her fear as a child from observing her own mother.) Did she feel abandoned? Did she think she was going to die or be severely harmed? Was there a pattern of gradual increase in distress and avoidance after each event of vomiting? Is one experience more relevant or distressing than others? Do any of these memories link to current ‘flashbacks’ that she might now be experiencing. If not, how often does she experience intrusive images of herself or others being sick (‘flash-forwards’)?

The vomiting history and any meaning attached to these experiences can be used for a developmental formulation of how the phobia has developed. Note that it may be difficult to identify any associations or meaning of vomiting from very early experiences and the only association is that of overwhelming fear.

Current history

Assessment measures

There are no published measures for measuring outcome in SPOV but the author is currently evaluating a Vomit Phobic Inventory, which is a 14-item self-report measure that focuses on cognitive processes, safety and avoidance behaviours that could be used weekly. The Emetophobia Questionnaire is a 21-item self-report questionnaire that has good reliability and validity against a behavioural avoidance test (Boschen & Riddel, unpublished observations). These authors have also devised a behavioural approach test that involves measuring how close a person is willing to approach a bucket containing fake vomit (created from a recipe).

Goals and valued directions

Clients with SPOV are often ambivalent about change when they first present. Their goals may be to lose their fear of vomiting but without really accepting the possibility that they might vomit in the future. Try to agree on specific goals about what will be achieved by the end of therapy (e.g. ‘I want to be able to go on holiday abroad’; ‘I want to be able to eat out at a restaurant with my family’; ‘I want to let my children got to school’). Try to negotiate goals that emphasize improving the quality of life and participating in activities that are important to them rather than ‘no longer feeling anxious about vomiting’ but which accept the possibility of vomiting in the future. Exploring their valued directions in life may help this, e.g. one domain might be in what way they want to be a good mother for their children despite their fear (Hayes et al. Reference Hayes, Strosahl and Wilson1999).

Psycho-education and engagement

The therapist should normalize the experience of vomiting as being an adaptive process that increases the client's chances of survival if she became ill. Information may be given about how vomiting is beneficial and prevents disease by getting rid of toxins. Thus the rat is the only animal that cannot vomit and one reason why rat poison is so effective.

People with SPOV may believe that if vomiting were to occur it would last for many days. Here the therapist can provide normative information on how long vomiting normally lasts for after an infection or food poisoning, this might be assisted by a survey of others about how long vomiting persisted when they were ill.

Others believe that they can influence or control their vomiting. However, the act of vomiting is a primitive reflex act that cannot be inhibited. People with SPOV tend to focus on the risk of infection or food poisoning but the reflex can be triggered by a wide variety of stimuli around the body (e.g. mechanically in gynaecological problems, a stretched gall-bladder or stomach or by certain drugs or metabolic problems that act on the brainstem, extreme fear, severe pain, certain smells). If a vomit reflex is triggered then it cannot be ‘controlled’. This is difficult to demonstrate in a behavioural experiment despite the above information.

Therapy begins with a developmental formulation. If there are early adverse experiences of vomiting they can be linked to current problems and discussed as ‘ghosts of the past’ that have not yet been updated. It is also worth the therapist emphasizing that developing a SPOV is highly understandable given the way that humans and animals can easily become averse to certain foods after, e.g. food poisoning or an infection, and avoid situations that remind them of vomiting. Validate the fact that vomiting in childhood can be very panic inducing (e.g. the association with the feeling of suffocation, choking or death). Explain that as an adult you know these associations are not true, although they remain powerfully linked in the mind. However, there are reasons to be optimistic because even things learned over many years can be ‘unlearned’ and many people with SPOV can overcome their problem or make it more manageable. Note that not everyone will be able to recall early adverse experiences of vomiting as they may no longer be accessible.

A client with SPOV is often reluctant to engage in any treatment that involves exposure to any risk of vomiting. She may have marked health anxiety and believe that she is especially vulnerable to vomiting or at a higher risk of vomiting compared to others. She may have received a diagnosis of irritable bowel syndrome or an allergy as an explanation for nausea and other gastrointestinal symptoms. Engagement may be assisted following the model of hypochondriasis (Clark et al. Reference Clark, Salkovskis, Hackmann, Wells, Fennel, Ludgate, Ahmad, Richards and Gelder1998), where a client is presented with two alternative hypotheses to test out in therapy. ‘Theory A’ (the one she has been following) is, for example, that she is more prone to vomiting and that she has an increased ability to control her vomiting. ‘Theory B’ is that the problem is of worrying excessively about vomiting and trying too hard to prevent herself from vomiting (for which the unintended consequences are her feeling that she is more vulnerable to vomiting; feeling more nausea from anxiety, or feeling she has control over her vomiting.)

The therapist might discuss metaphors about solutions (e.g. man in the hole; Hayes et al. Reference Hayes, Strosahl and Wilson1999). The emphasis in engagement is focusing on the how symptoms of nausea, the handicap and distress are maintained by avoidance, safety-seeking behaviours and excessive vigilance. Thus the goals in therapy for the client are to become functional and follow their important directions in life, as trying not to vomit has a significant cost and, as yet, no or little effect on the frequency of vomiting.

Maintenance model

Progress can be made to an understanding of the current processes that maintain the client's fear by drawing an idiosyncratic model (Fig. 1). Central to the model is the way a person with SPOV may (a) re-experience past memories of vomit or vomiting and fuse them with the present, (b) misinterpret nausea or thoughts and images of vomiting as evidence of impending vomit, (c) evaluate vomiting as 100% awful (see Fig. 1), (d) become more anxious and experience further sensations of nausea and gastrointestinal symptoms in a vicious circle.

Fig. 1. Maintenance of specific phobia of vomiting.

The model naturally leads to a dialogue about the role of safety-seeking and avoidance behaviours and the degree to which the client believes that her behaviours prevent herself from vomiting. The aim of therapy is to test Theory B, to enable the client to drop her safety- seeking and avoidance behaviours and act ‘as if’ the problem is of trying too hard to prevent herself from vomiting. Thus it is crucial to conduct behavioural experiments and enter situations and activities associated with nausea without self-focused attention and safety- seeking behaviours. This will involve allowing herself to experience intrusive thoughts and images of vomiting or sensations of nausea and then reducing safety-seeking and avoidance behaviours. In time this will reduce the nausea and improve the quality of life caused by the handicap (and make no significant difference to whether they vomited or not).

Not having control over a reflex act is a difficult concept for many people with SPOV who believe that if they are going to vomit they can prevent it from happening. This is an over-inflated sense of responsibility similar to that found in OCD and generalized anxiety disorder (GAD). Clients may believe that their safety-seeking behaviours have prevented them from vomiting in the past and are often proud of the number of years since they last vomited. Preliminary surveys suggest that the frequency of vomiting is no different in people with or without a vomit phobia despite a lifetime of trying to prevent themselves from vomiting. However, this needs replicating in a prospective study with a larger number of controls as a person with SPOV may have a better recall for when they have been sick. Vomiting from food poisoning or an infectious illness in an adult in a developed country is still a relatively rare event. Other events such as binge drinking or eating from a roadside stall in a third-world country may be associated with a higher risk of vomiting but are not something that you will be asking your client to do.

People with a SPOV may recognize the low probability of the likelihood of vomiting but continue to believe that the awfulness of vomiting is too great and do everything they believe necessary to stop themselves from vomiting (or even thinking about it). In this respect it has similarities with an over-inflated sense of responsibility and the need for certainty as in OCD (Salkovskis et al. Reference Salkovskis, Wroe, Gledhill, Morrison, Forrester, Richards, Reynolds and Thorpe2000). Many clients say that they would prefer to be in control and die rather than vomit. For this reason it may be more helpful to focus the individual on what she really wants her life to represent – rather than being someone whose life is dedicated to not vomiting or to following the values that were identified in her assessment. A person with SPOV is being asked to act as if they do not have a SPOV even if they believe that vomiting is awful or life threatening. This has many implications in trying to give up control over vomiting and accepting the uncertainty that vomiting may occur. It is helpful to explore the meaning or imagery associated with ‘losing control’ (e.g. the idea of not being able to prevent oneself from vomiting and the vomiting persisting). A major step for the client is accepting that if her body needs to vomit (e.g. food poisoning) then there is very little control in preventing vomiting (and it would be dangerous if one could inhibit removal of toxins). One can partly demonstrate magical thinking by a behavioural experiment in which the client is encouraged to wish herself vomiting when she feels nauseous or bloated. It is also possible to demonstrate the lack of control over intrusive thoughts and images of vomiting by standard thought control experiments (e.g. try not to think of a ‘pink elephant’). The message is that trying to control thoughts or feelings of vomiting is the problem that increases distress and not the solution.

For the client, the fear of losing control is related to the need for certainty that she is not going to vomit. As in OCD, this is questioned by pragmatism. There is no guarantee that whatever a person with SPOV does in therapy to overcome her fears will not be associated with vomiting (or it may occur by coincidence for another reason). However, the cost of failure to overcome her fear and trying to prevent herself from vomiting is the guarantee that she will be disturbed by a SPOV for the rest of her life and be unable to follow her valued directions in life.

Exposure in vivo

The evidence-based treatment for specific phobias is graded exposure in vivo. Graded exposure involves a hierarchy that is negotiated and exposure done in vivo within sessions or as homework alone or with the assistance of a relative or friend. The choice of cues for exposure will therefore be guided by the assessment, the hierarchy of cues and formulation. Some valued directions such as the need to increase weight or to be an effective parent for child care may also determine the priority of which tasks take greater priority.

The guiding principle for graded exposure in vivo in SPOV is to choose both (a) internal cues of vomiting (e.g. past memories of vomiting, thoughts, images or sensations associated with vomiting), (b) external cues for vomiting that are being avoided or devised for the treatment programme (e.g. smell of vomit). Graded exposure needs to be done without safety-seeking behaviours, self-focused attention and other attentional biases in monitoring nausea and other gastrointestinal symptoms. It needs to be done continuously until the anxiety has effectively subsided. Last, exposure means full acceptance that one has very limited control of any intrusive thoughts or images of the idea of oneself vomiting in the future. An example of an exposure hierarchy is shown in Table 2 and the client's history is given below.

Table 2. Example of exposure hierarchy

SUDS, Subjective Units of Discomfort Scale

Case history

Ms A is a 25-year-old single woman who is a student midwife. Her main problem is of herself vomiting but there is some fear of others vomiting because she may vomit from catching an illness or watching others vomit. She sought help after she escaped from a ward where a pregnant woman was vomiting. Her preoccupation with vomiting lasts about 5 hours per day. The onset occurred when she was 8 years old and it has been a significant problem for the past 5 years. She has not vomited for 15 years. She eats a restricted diet and has a number of the avoidance behaviours listed in Table 1. She has a number of aversive memories of herself vomiting aged 9 years and of her mother vomiting aged 12 years. Engagement occurred by developing a shared formulation of the problem by drawing an idiosyncratic model using information gathered from self-report measures and clinical assessment of the maintaining factors. She learnt how her responses to a fear of vomiting (her solutions of avoidance, safety-seeking behaviours, worry, self-monitoring and excessive vigilance of vomiting) was now making her more anxious and experiencing more nausea in a vicious circle. The costs on the patient's quality of life were discussed as well as the adaptive function of vomiting. The client's expectations of treatment and specific goals were derived by operationalizing the ability to act in her valued directions despite a fear of vomiting. She participated in exposure in vivo for various avoidance behaviours listed in Table 1 without her safety-seeking behaviours. She carried out imaginal re-living and re-scripting of past aversive experiences of vomiting. She learnt to stop monitoring her nausea and to give up trying to control her thoughts and sensations of nausea. She eventually did a role-play of vomiting using the smell of vomit and with a washing bowl of a vomit recipe. She felt she would always have a fear of vomiting but was able to return to being a midwife and to go out socially and eat food in restaurants despite her fear.

One can either use a rationale of habituation or a behavioural experiment paradigm. The rationale for habituation is that anxiety about vomiting (and therefore sensations of nausea) will decrease over time with increasing exposure. Behavioural experiments do not involve testing whether vomiting occurred or not (since a person with SPOV might discount their experience and believe that there is always a next time to vomit). The experiment is about determining whether the distress lasted as long as predicted or whether their experience best fits with Theory A or Theory B (see Psycho-education and engagement section on engagement). It may also assist in differentiating between the experience of nausea or other symptoms of anxiety and that associated with vomiting.

In most people with SPOV, the phobia is of themselves vomiting not of vomit. However, for exposure, it is impractical and unethical to induce repeated vomiting by the use of emetics or to self-induce vomiting. Indeed it could make a client even more determined never to vomit again and repeated vomiting could theoretically lead to electrolyte imbalances or dental damage. There might be exceptions for inducing vomiting in a one-off behavioural experiment in individuals who have never vomited, but in general I would not recommend induction of vomiting. If induced vomiting is used then it is important to report it as a single case experimental design with predictions about the nature of vomiting (e.g. rating of the awfulness) before the induction and then compared after vomiting. It is also vital for long- term follow-up to be reported. I am aware of one client with SPOV who had emergency abdominal surgery and vomited repeatedly post-operatively. She decreased her fear and rating of the awfulness of the vomiting but over the following year her fear and rating of awfulness returned to the previous level.

Vomit (or a verbal, visual, audio, olfactory or physical representation of vomit) may be a trigger that increases anxiety about vomiting. Exposure to such cues is therefore a means towards an end and can be incorporated into a hierarchy of graded exposure. This includes exposure in imagination to the client vomiting in the future. Existing case descriptions have focused on exposure in imagination to vomiting (Wijesinghe, Reference Wijesinghe1974; O'Connor, Reference O'Connor1983; Lydiard et al. Reference Lydiard, Laraia, Howell and Ballenger1986), simulated vomit (McFadyen & Wyness, Reference McFadyen and Wyness1983), joke vomit, or videos of others vomiting (Philips, Reference Philips1985; Lydiard et al. Reference Lydiard, Laraia, Howell and Ballenger1986). These are all valid and a common recipe is provided in Table 3 (McFadyen & Wyness, Reference McFadyen and Wyness1983). It may also be important to customize the recipe to resemble a previous experience (e.g. spaghetti bolognese).

Table 3. Recipe for vomit

Combining the exposure in imagination for vomiting with the smell of vomit is especially pungent. Butyric acid is responsible for the smell of vomit and can be purchased in a concentrated form from specialist suppliers over the internet (e.g. http://www.camlab.co.uk). It is also found naturally in rancid butter and Parmesan cheese. Locations of the natural smell of vomit include casualty departments in the early evening (especially children's area). The therapist and client may also role-play themselves vomiting with a plastic bucket with the recipe for vomit and added butyric acid.

Videos of others vomiting can be found by searching on http://www.youtube.com/ and http://video.search.yahoo.com/. A graded exposure programme to pictures of vomiting can be found on http://www.emetophobia.bravehost.com/. Other ‘resources’ include http://www.ratemyvomit.com/, although I am not sure about the value of pictures such as people sleeping in vomit. Although a therapist (usually male) may find the Mr Creosote scene in Monty Python's Meaning of Life very funny, it is probably not helpful for someone with a SPOV. Audio clips of vomiting can also be downloaded from the internet and placed on a loop.

The impact of exposure to auditory and visual cues of vomiting can be maximized by combining them with exposure in imagination to the client vomiting at the same time especially if memories of past experiences of vomiting are being avoided. For some people, touching pictures of vomiting and describing it as if they are vomiting can be helpful. Exposure can be made to the word ‘vomit’ and ‘vomiting’ or affixed as posters around the home. Repeating the word ‘vomit’ for several minutes may be helpful when the word is a term that is avoided or euphemisms are used.

Some clients report that watching simulated or real vomiting by others may not be sufficiently realistic and does not reduce rating the ‘awfulness’ of themselves vomiting. Special attention should be made whether the client is using neutralizing, self-reassurance or other safety behaviours believing that she can prevent herself from vomiting. Exposure can also be done to internal sensations that are cues to vomiting (Hunter & Antony, Reference Hunter and Antony2009). They include cues such as drinking a full can of a fizzy drink in one sitting and eating more at mealtimes to induce a sensation of bloatedness; holding mouthwash in mouth for 30 seconds and reading in a moving vehicle to induce a sensation of nausea.

Exposure in imagination and imagery re-scripting

If the client has identified intrusive imagery and aversive memories of vomiting as a child then the therapist may need to add exposure in imagination or as imagery re-scripting. The procedure is derived from Arntz & Weertman (Reference Arntz and Weertman1999) and Smucker & Dancu (Reference Smucker and Dancu1999). It has not yet been evaluated in SPOV but the procedure has been successfully used in social phobia (Wild et al. Reference Wild, Hackmann and Clark2008) and other anxiety disorders. Clients are asked to describe their aversive memory in three stages. The first stage involves re-living the aversive memories from the age when they first experienced vomiting. This consists of exposure in imagination and should be described in the first person, present tense and from a field perspective in as much detail as possible. The client should first state their age and the context. Recounting the memory should be done in slow motion like a video frame-by-frame account. Ensure that there are no ‘hot spots’ that are being avoided and if necessary ask the client to describe in more detail those aspects which are more anxiety provoking. She should describe the sensations of the vomiting as well as the colour, taste and texture of the vomit. Ask the child to describe the meaning of the experience and what the child needs or would like to happen next. This allows the meaning of the event to be updated in the next phase of repeating the memory from an adult's self-perspective. (For further details of imagery re-scripting see the above references.) A variation on imagery re-scripting is ‘Competence Imagery’. This is described by Moran & O'Brien (Reference Moran and O'Brien2005) in a girl who avoided social environments because she feared encountering vomit or others vomiting (and was not therefore typical of people with SPOV). Therapy included systematically pairing anxiety-provoking conditioned stimuli (video scenes of someone vomiting) with competence images. The client chose to imagine playing her musical instruments, swimming lengths in the pool, or practising yoga postures, which were actions she believed she could perform well. Theoretically this could be used in others with SPOV with exposure to cues associated with vomiting.

Dropping safety behaviours

Safety-seeking behaviours will interfere in exposure and are the main obstacle to progress. The goal is to drop all the responses that are believed to maintain the fear. This includes cognitive processes such as worry and attentional biases towards potential risks. If you identified the meta-cognitions about the cognitive processes (e.g. ‘It can help me mentally prepare myself for vomiting’), then these can usually be challenged pragmatically on the basis of their unintended consequences and their costs (e.g. ‘How effective is worry at mentally preparing yourself? Is this something you would teach others? If not, why not?; What is the cost of mental planning?’).

Dropping of safety-seeking behaviours and self-focused attention may be assisted by behavioural experiments in which the behaviour is either increased or decreased and asking the client to make specific predictions. Does the use of a safety-seeking behaviour or compulsion increase or decrease her worry and distress about vomiting? Does focusing her attention internally and monitoring the level of nausea increase distress compared to focusing externally? A similar approach can be used for compulsions. Some clients excessively check the freshness of food, have abnormal hygiene measures, check excessively health of themselves and others, follow superstitious behaviours, repeatedly seek reassurance, perform excessive cleaning of kitchen area and toilet. Compulsions are identified and can be added to the hierarchy for them to be discontinued. Similar to people with OCD, it is usually important to identify the termination criteria for a compulsion (e.g. feeling comfortable) that are problematic in maintaining the behaviour and to ensure that if a compulsion is conducted, then the patient ‘undoes’ it by re-exposing herself to the original risk.

For fears of negative evaluation by others about vomiting, the therapist may suggest their client conducts a survey of attitudes towards someone else vomiting who is ill. The client should make her predictions first and then ask others how repulsive they would find someone else vomiting, or for how long they would be repulsed, or the degree to which a person would make a fool of themselves. A therapist may role-play vomiting with fake vomit and take a survey of people passing.

Pharmacotherapy

There is no evidence base for the use of pharmacotherapy in specific phobias, but there might be a rationale for a selective serotonin reuptake inhibitor (SSRI) in those with severe symptoms that overlap with OCD and who are unresponsive to CBT. Nausea is a potential side-effect of a SSRI which might be used as a form of exposure or may mean that it is an unacceptable approach.