Normal and abnormal are extremely hard to define. Someone who is abnormal is usually different from the majority or deviates from the average.

Factors which influence what is defined as normal or abnormal are:

  • Culture - some cultures are built on people being part of a community whereas some allow people to be more independent
  • Situation - the situation can make a difference as to if something is normal or abnormal, chanting is not acceptable in a church but at a football game
  • Gender - expectations of gender mean some things are accepted in one gender but not in the other such as makeup
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Definitions of abnormality

Statistical deviation is when an individual has a less common characteristic such as being less intelligent or more depressed than the majority of people.

The avergae IQ is 100. 65% of people have an IQ between 85 and 115. Only 2% have an IQ lower than 70. Those who have an IQ of 70 or less are usually described as 'abnormal' and will be diagnosed with intellectual disability disorder (used to be known as mental retardation).

Deviation from social norms is when someone displays behaviour that is different from the accepted standards of behaviour in a community or society.

Someone with antisocial personality disorder (psychopathy) is impulsive, aggressive and irresponsible. We see a psychopath as abnormal because they don't conform to our morals. 

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Evaluation of definitions

  • Statistical deviation has real-life application seen in the IQ and intellectual disability disorder. Clinical assessment of patients who have mental disorders will be compared to statistical norms rather than social norms. 
  • Many people view unusual characteristics as undesirable to have but if someone has a much higher than average IQ that will be viewed positively. This shows statistical deviation shouldn't be used alone to diagnose someone as they may be one of the minority but their characteristic ca be positive and not need treatment.
  • Statistical deviation can also be a setback as someone may have a very low IQ but still live a happy life, so the label may affect them in a negative way as it may make them feel differently about themselves.
  • Deviation from social norms won't be a sole explanation for someone's diagnosis. While it is used to help diagnose antisocial personality disorder, there are other factors (such as failure to function adequately) which may explain their disorder, not just deviation from social norms.
  • Social norms vary in different cultures so what is accepted in one culture may not be in another. 
  • If we rely on deviation from social norms too much as an explanation because it could lead to systematic abuse of human rights. Historical examples show diagnosed conditions such as drapetomania which was simply black slaves who ran away. Because it wasn't the norm for slaves to run away at that time they felt they had to diagnose a condition for it because it was seen as abnormal.
  • Deviation from social norms does take into account the desirability of a behaviour which statistical deviation doesn't. Being extremely clever isn't seen as a deviation from social norms because it is it viewed positively whereas according to statistical deviation it would be a bad thing.
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Definitions of abnormality

Failure to function adequately is when someone is unable to cope with the demands of everyday life. If the individual is distressed or people around them are distressed because of their behaviour then this failure to function adequately.

One researcher came up with 7 behaviours that determine if someone is failing to function adequately: suffering (if they or someone around them is suffering), maladaptiveness (failing to have fulfilling relationships or keep/have a job), unconventionality (unusal behaviour), loss of control, irrational (way of behaving), observer discomfort (when the person observing them feels discomfort from their behaviour) or violation of moral standards.

Deviation from ideal mental health is when someone doesn't meet the criteria for good mental health. 

Maria Jahoda (1958) came up with 8 criteria to show what good mental health should look like: No symptoms of distress, rational and can percieve themselves accurately, self-actualise (reach potential), can cope with stress, has a realistic view of the world, has good self-esteem and lacks guilt, independent of people and can successfully work, love and enjoy pleasure.

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Evaluation of definitions

  • Failure to function adequately does include the perspective of the individual. Although it is difficult to assess distress, it still attempts to capture the experiences of the patient. As it looks at people's individual experiences, it then helps psychologists to look at abnormality through the eyes of people who have experienced it.
  • Some people who we believe to be failing to function adequately may just be deviating from social norms. Some people like New Age Travellers do not work or have permanent housing, many people may see that as failing to function adequately but it is a choice they have made.
  • Someone has to judge if a patient is distressed to decide if they are failing to function adequately. Some people may be distressed but not suffering. The psychiatrist has the final judgement.
  • Jahoda's criteria covers a huge range of issues. Many of them are reasons why someone would go to seek mental health help. It is a good tool to use for thinking and talking about mental health.
  • Western European and North American people follow individualistic cultures where we put ourselves at the front of a lot of things we do. Other cultures focus on the importance of community and family so much of the world would see our independence as a bad thing.
  • The criteria of Jahoda is very unrealistic for someone to follow all of the ideas on the list.
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A phobia is described as an irrational fear of an object or situation.
There are three categories of phobias in the DSM-5:

  • Specific phobias are fears of specific objects or situations e.g. arachnophobia is fear of spiders, aerophobia is fear of flying, claustrophobia is the fear of small spaces, etc
  • Social phobias are the fear of humiliation in public places such as fearing eating in public, using public toilets or public speaking; embarrassment is the main concern
  • Agoraphobia is the fear of public places such as shopping centres or crowded streets. It seems to be social phobia at first but this phobia brings extreme panic attacks and makes the sufferer feel impending doom and fears dying, going mad or losing control; safety is the main concern of the individual

These diagnostic features of phobias are things the doctor will look out for when diagnosing someone with a phobia:
☆ Intense, persistent, irrational fear of a particular object, event or situation
☆ The response to the stimuli is disproportionate and leads to avoidance of phobic object, event or situation
☆ Fear is severe enough to interfere with everyday life

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Characteristics of phobias

Behavioural characteristics:
Panic - May panic when they see the stimulus, this could be screaming, crying or running away. For children it may be that they freeze, cling to a parent/carer or have a tantrum.
Avoidance - Goes to efforts to avoid any situations which may involve contact with their stimulus.
Endurance - Sufferer remains in the presence of the stimulus but experiences high anxiety.

Cognitive characteristics:
Selective attention to the phobic stimulus - The sufferer struggles to look away from stimulus.

Cognitive distortion - Sees phobic stimulus in a dangerous or ugly way when it may not be.
Irrational beliefs - May hold irrational beliefs regarding their stimulus which increases pressure on sufferer

Emotional characteristics:
Anxiety - Can't relax and finds it difficult to experience anything positive, can be long-term.
Emotional responses are unreasonable - May see tiny spider as harmful when it's not.

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Depression is classed as a mental disorder characterised by low mood and low energy levels.

For someone to be suffering with clinical depression they need to have been suffering with five or more symptoms for over two weeks, the symptoms include:

  • Poor/increased appetite and weight loss/gain
  • Sleep difficulty or sleeping too much
  • Loss of energy
  • Body slowed down or speeded up
  • Loss of interest in usual activities
  • Feelings of self-reproach, excessive or inappropriate guilt
  • Inability to concentrate or think clearly
  • Recurrent thoughts of death, suicide or suicidal behaviour
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Characteristics of depression

Behavioural characteristics:
Activity levels - Will have reduced activity levels and they may withdraw from work, education and socialising
Disruption to sleep and eating behaviour - May experience insomnia or hypersomnia (increased need for sleep) and appetite may increase or decrease
Aggression and self-harm - May become aggressive and may self-harm or make suicide attempts

Cognitive characteristics:
Poor concentration - Unable to stick to a task or find it hard to make decisions they normally make
Dwelling on negative - Focus more on the negative aspects of something 
Absolutist thinking - See situations as black and white, either all-good or all-bad

Emotional characteristics:
Lowered mood - Feeling lethargic, sad, worthless and empty
Anger - May regularly feel anger either towards themselves or towards others
Lowered self-esteem - Sufferer may self-loathe

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OCD is a disorder that is characterised by obsessions and/or compulsions.

The DSM-5 recognises different types of obsessive behaviour disorders:

  • Trichotillomania is compulsive hair pulling
  • Hoarding disorder is when a sufferer compulsively gathers possesions and struggles to get rid of anything, regardless of how small and insignificant it may seem
  • Excoriation disorder is compulsive skin picking

 OCD works in this cycle: Obsessions are intrusive thoughts and urges which cause anxiety. The sufferer usually worries that something will happen to them or their family/friends. Most sufferers know their obsessions are irrational. Compulsions are the reactions to these obsessions, they are usually rituals the sufferer carries out to relieve their anxiety. Most of the time the sufferer knows their compulsion is irrational. A sufferer's obsessions and compulsions are not always linked, for example, a girl thinks if she doesn't tap her surroundings then her family will be harmed, however tapping things doesn't actually help to keep them safe.

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Characteristics of OCD

Behavioural characteristics:
Repetitive compulsions - sufferers feel the need to do their repeat their compulsions many times
Compulsions reduce anxiety - people feel compulsions reduce anxiety from obsession
Avoidance - many sufferers will try and avoid situations where there may be a trigger

Emotional characteristics:
Anxiety and distress - both obsessions and compulsions can cause anxiety, sometimes the sufferer may have anxiety from not being able to carry out their compulsions
Accompanying depression - some sufferers will also experience depression
Guilt and disgust - guilt could be towards something small and disgust could be directed to self

Cognitive characteristics:
Obsessive thoughts - thoughts which occur repeatedly, they are unpleasant
Cognitive strategies to deal with obsessions - people find ways to deal with their obsessions such as prayer if a religious person feels tormented, this may make them seem abnormal to others
Insight into excessive anxiety - sufferers are aware their obsessions/compulsions are irrational however they do them as they feel the worst case scenario (family will die if I don't touch this) justifies their actions

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The two-process model

The two-process model is the behavioural approach to explaining phobias. The model was developed by Mowrer (1960). It says that phobias are aquired by classical conditioning and maintained by operant conditioning:

Classical conditioning:
John Watson and Rosalie Rayner (1920) done an experiment where they created a phobia of rats on a 9-month old child Little Albert. The noise was an unconditioned stimulus which created an unconditioned response of fear. The rat was the neutral stimulus and created no respone. When the rat and the noise were put together there was a response of fear. This mean the rat became the conditioned stimulus and produced the conditioned response. He then also became scared of similar objects such as a non-white rabbit and a fur coat.

Operant conditioning:
Operant conditioning is learned by being rewarded or punished. A person with a phobia will then start to avoid the situations where there is the "punishment" and their phobia is maintained as they are not put in a situation that is scary for them. They know by avoiding the situation they don't have anxiety, so they choose to repeat the avoidance.

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Evaluation of the two-process model

  • The idea is praised as it is a step forward for explaining phobias. It helped improve therapy as therapists started to recognise that they need to expose the patient to the phobia for them to get over it.
  • Bounton (2007) recognises that the model actually ignores evolutionary factors. Some phobias are there because they were adaptive such as fear of heights or snakes, we need to be scared of these things to survive.
  • Some phobias have not followed a trauma as Mowrer suggests. Some people have phobias without knowing about a bad experience with the stimulus in the past.
  • The model does have ethical issues as it suggests that people are to blame for phobias, for example if a parent took their child out and the child got barked at by a dog, they may then have a phobia of dogs but essentially people could blame the parents for taking the child near a dog in the first place.
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Systematic desensitisation

Systematic desensitisation (SD) is one behavioural approach to treating phobias. SD works by gradually reducing the anxiety a sufferer has from their phobic stimulus. This is done with the same principal as classical conditioning; they learn a different response to their phobia, this process is called counterconditioning. SD works by following three steps:

1. The anxiety hierarchy: A list of situations put together by the patient and therapist to understand which situations involving the phobic stimulus give the most and least anxiety to a patient. For example a patient with arachnophobia would feel more anxiety seeing a spider near them than seeing a picture of a spider.

2. Relaxation: The therapist teaches the patient ways to relax through breathing exercises and mental imagery techniques.

3. Exposure:  This is when the patient is actually exposed to their phobic stimulus while relaxed. This needs several sessions as they start at the bottom of the anxiety hierarchy and work their way up until the patient can be at the top of their anxiety hierarchy and feel relaxed.

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Evaluation of systematic desensitisation

  • It has been proved as an effective way of treating phobias. Gilroy et al. looked at 42 arachnophobic patients who had three 45 minute sessions. There was a control group who were treated with relaxation without exposure. They were all assessed at 3 months and 33 months after their treatment. The systematic desensitisation group were less fearful than the control group, proving it is effective and long lasting.
  • Other therapies like flooding and cognitive therapies may not be suitable for all patients whereas most patients will take part in SD. For example, some sufferers of phobias may have learning difficulties and may not understand what is happening during flooding and it could be quite traumatic for them. 
  • A lot of patients prefer SD over flooding, as the relaxation techniques can be relaxing for patients. There are low numbers of people refusing to start SD and dropping out of SD.
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Flooding is another behavioural approach to treating phobias. Flooding works by the therapist completely exposing their patient to their phobic stimulus without having taught relaxation techniques. By doing this it should show the patient there is nothing to be fearful of and should lead to the extinction of their phobia. An example would be an arachnophobe having a spider crawl over their body. It usually only lasts one session but can take up to three hours.

Some people may see this therapy as unethical, but it is not as it requires the patient to know exactly what they are going to do and giving full consent. 

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Evaluation of flooding

  • It is a cost-effective treatment as it is quicker and highly effective. As the patient is free of their symptoms quickly, they don't have to have follow up sessions.
  • It is less effective for certain types of phobias such as social phobias. People with social phobias think unpleasant thoughts about the situation itself which is congitive so they may be better having cognitive therapy.
  • The treatment can be traumatic for patients. Some patients do not see their therapy through to the end so it doesn't work properly and may be more traumatic than helpful. It can be a waste of money and time if the patient stops half way through. 
  • There is also the idea of symptom subsitution which is when one phobia is treated but soon replaced with another phobia. The evidence for this is very mixed.
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Beck's negative triad

Beck's negative triad (1967) is one of the cognitive approaches to explaining why some are more vulnerable to depression than others. Beck suggested there are three parts to explaining why some people are more vulnerable than others:

Faulty information processing: Someone who is depressed will focus on the negatives of a situation and ignore anything positive. They will see things in black and white. One example is if someone won £1 million on the lottery, they would focus on the fact that someone won £10 million the week before.

Negative self-schemas: A schema is a group of ideas created through experience. A self-schema is ideas about oneself. This means someone who is depressed and has negative self-schemas interprets information about themselves in a negative way.

The negative triad: This is the dysfunctional view an individual has of the world, their future and themselves. A depressed person would have negative views of the world, they would see the world in the worst way possible and focus on all the bad things like war rather than the good things. They would also have negative views about the future and believe that nothing is going to get better for themselves or others. Finally they would have negative views on themselves and may see themselves as a failure and have low self-esteem.

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Evaluation of Beck's negative triad

  • Beck's theory has good supporting evidence. Grazioli and Terry (2000) done a study on 65 pregnant women to assess their cognitive vulnerability and depression before they gave birth. Their results found that the women who were judged as high in cognitive vulnerability were more likely to suffer with post-natal depression.
  • His negative triad has been applied to CBT (cognitive behavioural therapy) and formed the basis of CBT. His negative triad allowed therapists to understand how to challenge people with depression on their thoughts and views on the world. It helps create successful therapy.
  • It does have a limitation; it explains the basic symptoms of depression but because depression is complex some people can't be treated using his idea. Patients that are angry of suffer hallucinations cannot be explained or helped with Beck's idea easily.
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Ellis's ABC model

Albert Ellis (1962) has a different cognitive explanation for depression. He suggests that good mental health is the result of rational thinking so poor mental health such as depression and anxiety is the result of irrational thoughts (thoughts that interfere with us being happy and free of pain). The ABC model is there to show us how these irrational thoughts affect our lives:

Activating event - This is the triggering event which causes the irrational beliefs. This may be something like losing a job.

Beliefs - This is how the person feels because of the event. If they have lost their job they may believe they are worthless and a failure.

Consequences - This is how the person will react in the end because of the event and beliefs. If they lost their job and feel worthless, they may not bother to look for another job and give up.

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Evaluation of Ellis's ABC model

  • It can only explain reactive depression (depression that arises after an activating event) but doesn't explain the depression without an obvious triggering event. This makes it a partial explanation for depression.
  • It has led to successful therapy by challenging irrational negative beliefs. Lipsky et al. (1980) produced effective research to support this idea.
  • This theory has the same limitations as Beck's theory as it doesn't explain the anger experienced by some patients or why some people suffer with hallucinations and delusions.
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Beck's cognitive behaviour therapy

Beck's cognitive behaviour therapy (CBT) is one cognitive approach to treating depression. CBT is used to tackle the way the patient thinks. Beck's CBT works by challenging the individual's negative triad.

The therapy will first look at the negative thoughts the individual has about the world, then the views they have of the future, then finally the negative views they have on themselves. The patient may also be asked to go home and do tasks like recording times when they enjoyed themselves or when others were nice to them so they have this to reflect on when they feel down.

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Evaluation of CBT and REBT

  • March et al. (2007) proved the effectiveness of CBT by doing a study on depression patients which compared the effects of CBT, anti-depressants and a combination of both. After 36 weeks he found 81% of the only CBT and only anti-depressants group saw an improvement. 86% of the CBT and anti-depressant group saw an improvement. This proves the effectiveness of CBT, but shows it is more effective with anti-depressants.
  • For some patients, CBT is not effective as their depressions is too severe so they need medication first then will have CBT when they become more motivated.
  • Success may be down to the patient-therapist relationship. The relationship must be good for it to be successful.
  • CBT is not a quick fix for depression as each patient has 5-20 sessions. For someone with severe depression who may be suicidal, they will need medication to get better quickly.
  • Clients may be non-cooperative or become dependent on their therapist.
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Ellis' rational emotional behavioural therapy

Ellis' rational emotional behavioural therapy (REBT) is another cognitive treatment for depression. This treatment works by extending Ellis' ABC model. The ABC-DE model works for treatment as it makes the patient think about the Activating even, their Beliefs because of it and the Consequences of their beliefs. The extended model also Disputes irrational thoughts and beliefs held by the patient and evaluates the Effects of their new beliefs.

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Genetic explanations for OCD

Genetic explanations are one way of explaining OCD. Genes are one factor which can lead someone to OCD or being vulnerable to it. Lewis (1936) observed his OCD patients and found that 37% had parents with OCD and 21% had siblings with OCD. This suggest our likelihood of OCD increases if we have immediate family with the condition, but doesn't mean we will definitely have it if our family do. The diathesis-stress model says certain genes leave people more likely to suffer certain mental disorders, rather than definitely having it. It needs an environmental trigger to start the condition.

There are certain genes which have been found that create vulnerability to OCD which are called candidate genes.

OCD seems to be polygenic which means more than one gene is responsible for causing vulnerability to OCD. Taylor (2013) said that up to 230 genes may be involved in OCD.Genes that have been studied have links to serotonin and dopamine, both of which are transmitters that have a role in regulating mood. 

It is also believed that different genes cause different types of OCD. There is evidence that suggests particular genetic variations can cause different types of OCD such as hoarding or religious obsession.

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Evaluation of genetic explanations for OCD

  • Nestadt et al. (2010) done research which shows 68% of identical twins with OCD parents shared OCD as opposed to 31% of non-identical twins. This evidence shows the effect that genetics has on having OCD.
  • Psychologists have not been successful in finding all of the genes involved which could be because there are so many genes that are involved and genetic variations also affect the chances of having OCD. Genetic explanation isn't as strong as we thought as it doesn't tell us much.
  • Cromer et al. (2007) found half of their OCD patients had a traumatic event in the past and that OCD was more severe in those who had more than one trauma. This shows how much environmental triggers do influence OCD like the diathesis-stress model said.
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Neural explanations for OCD

The genes that have been associated with OCD are likely to effect the levels of key neurotransmitters as well as the structure of the brain. 

The role of serotonin (a neurotransmitter) is important in someone with OCD. If a person has low levels of serotonin then the normal transmission of mood-relevant information doesn't take place and as a result, mood and other processes are affected. At the least, some cases of OCD can be explained by the role of serotonin.

Certain cases of OCD are associated with impaired decision-making systems, in particular hoarding. This is to do with abnormal functioning lateral, frontal lobes. The frontal lobes are responsible for logical thinking and making decisions. There is further evidence which suggests the left parahippocampal gyrus area which is associated with processing unpleasant emotions, can function abnormally in someone with OCD.

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Evaluation of neural explanations for OCD

  • There is evidence that supports the role of neural mechanisms in OCD. Anti-depressants work by increasing levels of serotonin which suggests serotonin is involved in OCD. Nestasdt et al. (2010) done research to show that OCD symptoms form part of a number of other conditions that are biological in origin such as Parkinson's disease. It suggests that biological processes cause symptoms in those conditions may be responsible for OCD as well.
  • Studies about decision making have shown the same neural systems are the ones that function abnormally in OCD by Cavedini et al. (2002). But they've identified other systems that are sometimes involved so no system has been found that always plays a part. This makes it difficult to claim that we understand the nerual mechanisms involed in OCD.
  • There is evidence that shows neurotransmitters and structures of the brain don't work properly in patients who have OCD. But it is not the same as saying that these abnormalities cause OCD. They could be a result of OCD.
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Drug therapy

Drug therapy is used as a way of increasing/decreasing levels of neurotransmitters. OCD drugs are used to alter the levels of serotonin.

The standard medical treatment given is a type of anti-depressant known as selective serotonin reuptake inhibitor (SSRIs). They work on the serotonin system in the brain. The SSRIs stop the reabsorption and breakdown of serotonin which increases the levels of serotonin in the brain and stimulate the postsynaptic neruon. The postsynaptic neuron compensates for the reduction of functioning serotonin in the brain.

There are alternative drugs available if SSRIs don't work for an individual. Tricyclics and SNRIs are the two other drugs. Tricyclics are older types of the drug. Clomipramine is one type of tricyclics and it has the same effect on the body as SSRIs do but it has side effects which means it is only available to someone who has tried SSRIs first. SNRIs (serotonin-noradrenaline reuptake inhibitors) are a more recent type of anti-depressant. They are a second choice to SSRIs like tricyclics are but they also increase noradrenaline as well as serotonin. 

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Evaluation of drug therapy

  • Drug therapy has been proved as effective. Soomro et al. (2009) reviewed studies which compared SSRIs to placebos in treating OCD. All 17 studies he reviewed showed better results for SSRIs than placebos. Symptoms decline by 70% of patients that take SSRIs.
  • Drugs are more cost-effective than psychological treatments which is good value for the NHS and better for the economy. As well as this, it is non-disruptive to the patient's life. The SSRIs are not like therapy where the patient has to wait for it and it means the patient doesn't have to talk about their feelings if they don't want to.
  • The drugs can have side effects and some people may not benefit from the drugs at all. Some of the side effects include irritability, sleep patter disturbance, loss of appetitie and headaches. Some argue that the side effects are worse than the OCD itself.
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