Paranoia

Wikipedia defines Paranoid as a "thought proces believed to be heavily influenced by anxiety or fear, often to the point of irrationality."
It's as good a definition as any.  Freud stated though that a "man who does not lose his reason over certain things can have no reason to lose" (Freud 1895).
Paranoia is therefore considered a useful developmental 'defence' or 'stage'.  Fear of alieness is self protective. Discrimination is healthy and beneficial to individuals and the species.  Immunology is essentially the biological science of the 'same' and the 'other'.
In psychoanalytic psychiatry Rycroft 1968 describes paranoia as " a functional psychosis characterized by delusions of grandeur and persecution, but without intellectual deterioration. In classic cases of paranoia, the delusions are organized into a coherent internally consistent delusional system on which the patient is prepared to act."
Paranoia is seen in several modern DSMIV-tr diagnosis.
Paranoid Disorder is a specific persecutory delusional state that is relatively fixed.  Patients will say that they believe they are being followed.  They believe people are talking about them. They believe that people are watching them.  What's significant in the grandiosity involved.  A standard question is 'why would they be watching you."  Tied into the paranoia is an inferiority complex with egomania for sure. I remember a cleaning lady who believed the RCMP had invested millions of dollars in watching her, surveillance being a very costly affair.  Addressing this she expressed a sense of wonder but wasn't rational about the obvious discrepancy about her mundane life and the belief that it warranted dozens of men in uniform following her every day.
Paranoid disorders aren't usually associated with hallucinations.  If these are present we consider the diagnosis of Paranoid Schizophrenia instead.
In Paranoid Disorder there's a often a believable thead despite the over the top character of the concern.  A person might have a specific conspiracy theory. In one case a man believed his boss was persecuting him despite his leaving the firm a year before.  Another woman believed her ex husand was spying on her in the bathroom.  A tragic man who had been in a concentration camp believed the nazis were still watching him.
Mostly these people are highly functional and capable unless their paranoid delusional state was addressed. The son of the man who'd survived the concentration camp said his father was fine so long as no one mentioned Nazi's or the news didn't focus on Germany.  If something triggered his delusional state he was convinced the neighbours were spying otherwise he was able to go about work and care of family without much evidence of this very disturbed 'corner' or 'compartment' of his mind.
Paranoid Schizophrenia is more commonly more dispersed and often coupled with hallucinations. Whereas paranoid disorders often remain constant with often poor response to medication, paranoid schizophrenia can respond well to antipsychotics such that the patient will realize and have insight into their previous pre medication insaniety.  With paranoid disorders medications have modified the level of concern but mostly the patients have felt their ideas were true but that perhaps they'd 'reacted poorly'.  'Still it's true what I said.'
Paranoid Personality Disorders are persons who don't have frank delusions or hallucinations but persist in maintaining the idea that they are the subject of persecution.  They see the world in black and white, us against them.  They do well in oppositional parties, cults and marginal church organizations.  These institutions can give them a place to 'associate'. Any group association can generally help to modify these people.  Alone they tend to maximize their bizarre ideas.   More often than not they are loners. These people insist that Jews are controlling the world. If not the Jews it's the Conservative Government of Canada, the Democrats, or the Republcians in the States. Sometimes the identified enemy is anyone that will help maintain the person's paranoid position of one downmanship. The secondary gain in paranoid personality disorders is evidenced in the power that individuals and groups who function as paranoid can bring to their cause.  Indeed media these days is often seen as promoting paranoid personality disorders.  Once drug dealers ravaged America with marijuana smokers and jazz muscians seeking the daughters of the wealthy today it's just terrorists in general.  There's always an element of truth in paranoia and the more discrete the more alluring.
One interesting paranoid disorder is 'pathological jealousy'.  This is the situation where a person will believe everyone is out to get their mate and that their mate is out to betray them with everyone else.   Again there's a combination of inferiority complex and egomania.  There's narcissism and entitlement and often some reason for the concern.
Medications are highly beneficial with paranoid schizophrenia. The original meds for this condition were Chlorpromazine and haldol.  While these medications are still used especially in institutions newer major tranquillizers have been developed with less side effects and greater specificity for the neurochemical deficit.  Dopamine channels are thought to have been overworked, defficient or imparied and the medications restore the brain chemistry to the appropriate balance. Modern research shows that different areas of the brain are 'overfiring' and the inhibitory channels aren't working appropriately.  Untreated modern scans show that the brains of paranoid schizophrenics increasingly lose matter with late stage subjects showing enlarged ventricles and decreased frontal lobe functioning.  Early psychosis units are now the mainstay of treatment with recommendations for early intervention.
A brief psychotic episode lasts weeks to months.  Schizophrenia is definitely diagnosed when a person has a year of delusional thinking especially if this persists despite medication and therapy.
Paranoid disorder is ameliorated with medication.  The newer medications for treatment of paranoia in general are much better tolerated with little or no side effects in the low dosages which are usually most beneficial.  These medications include rispiridone,olanzepine,  seroquel (quitiapine), abilify (aripiprazole) and ziprasidone.  Sometimes patients will need just the least amount of medication whereas others need a much higher dosage. Medication is titrated against an identifiable sympton.  A person who won't go out of the house because they're sure that the devil is going to get them this day may well return to work and activities and church without the extremely persecution on any of the above medications. It's as amazing to see the restoration of function of people tragically brought down by mental illness.  Medications in this sense are like insulin and digitalis in terms of the break throughs and advances they have provided individuals.
Interestingly there is a depressive disorder which is associated with paranoia.  In the above cases paranoid disorders and paranoid schizophrenia and delusional jealousy don't respond to traditional antidepressant medications.  Paranoia as noted is neurochemically seen as related to dopamine receptors whereas depression is most associated with serotonin and noradrenaline receptors.  However in psychotic depression, the particular form of depression associated with paranoia a person can indeed have essentially two overlapping disorders. The treatment is first to treat the depression but to modify depression treatment with the combination of the medications already noted. Abilify works well in this regard but if insomnia is a problem seroquel commonly is coupled with the antidepressant medications for benefit.
Paranoid personality disorders don't respond to medications generally. If they do it's usually the lowest dose of one of the atypical antipsychotics.
I've mentioned medications first because paranoia, even more severe intransigent monosymptomatic delusional disorder where the paranoia is highly specific and highly resistant to change, can respond to medication.  Medications in these group of patients often are the first step in treatment and can often allow a person to overcome their paranoia to enter into some form of therapeutic alliance.
Sadly today given the litiginous society we live in , paranoids are often the prey of unethical lawyers.  Police often have a 'frequent flyer' list of paranoids in the community who commonly call the police for help when they experience delusions.  One of my patients, well known to the police. often wakes in the night convinced that some famous actor has raped her.  She herself is very beautiful and it was a concern initially because she falsely accused a star who indeed was in town making a movie. There was no association and no consequence, the star being a mensch of the first order despite the threat and potential damage.  Shortly thereafter it was recognised that the patient was being raped by men who were clearly not in town and often not on the continet. A classic paranoid disorder medication had a limitted benefit but if she was under stress for any other reason this delusion might resurface despite the medication.  I was thankful that my treatment years back reduced her phone calls to the police from weekly to only a couple of times a year.  As a truly lovely and sophisticated lady she was deeply perplexed by these decreasing episodes and definitely remorseful about her causing trouble.  As a result she was highly compliant with medication and had a very good result last I heard.
Psychotherapies have not been particularly beneficial for paranoid disorders.  I've treated a few with one on one psychoanalytic therapy or cognitive behaviour therapy with the principle concern being, not allowing one to get caught up in the person's delusional system.  Normally the junior doctors do just this.  With paranoids you're the greatest friend as long as you thoroughly agree with them that the Conservative Party of Canada or the CIA or Catholics are malevolent and likely to be out to get this poor persecuted individual.  However once you challenge this premise you are rejected and seen to be part of the conspiracy and in fact more confirm the diagnosis.  Given this many psychopharmacologists limit therapy to focus on the brain disease with far greater benefit than inexperienced therapists who think that by exploring the person's past they will 'solve' the paranoia.  There is often 'trauma' but just addressing the trauma doesn't necessarily resolve paranoid disorders as it might resolve a ptsd or depressive disorder.  R.D. Laing who worked with schizophrenia wrote a book called 'knots'.  It was mostly poetry but the metaphor as it applied to paranoia and for him paranoid schizophrenia is that the knot is very good and very tight.
There is an attempt today with dialectic therapy, a new form of psychotherapy based broadly on the philosophical ideas of Marxism and showing some benefit in the treatment of paranoia. I confess I find this not a bit ironic since Marxism - Lennonism has been seen to be one of the greatest paranoid structures wholly reliant on the evil 'capitalist' . McCarthyism was a similar competing paranoid system.
Group therapy has been beneficial but only in the traditional low level 'supportive' way.  There is alot of 'rage hidden in the paranoia and commonly it is a a person with a quiet form of paranoid disorder that one day goes 'postal'.
My own exposure to an excessive amount of paranoid spectrum disorders is because I work in addictions.  All of the chemical addictions increase paranoid tendencies. The alcoholics are forever persecuted by usually the wife, boyfriend, government or boss or parents.  "If you were married to my wife, you'd drink like me."  There's tremendous self pity and grandiosity as every alcoholic is described as a 'legend in their mind', their depression being the greatest, their suffering monumental.  Alcoholism results in regression of defensive and coping mechanisms to an adolesecent stage with clear cut splitting of 'good guys - those who let me drink, and 'bad guys; , those who interfere with my drinking. All the pathological jealousy I've seen has been associated with alcoholism.  This might well explain the success of soap operas given the plops so often reflect the behaviour of alcoholics.  This indeed made Two and a Half Men a tremendous parody until Charlie Sheen's had his Purple Rose of Cairo meltdown.
Drug abuse is an even more associated with paranoia.  Most often this is directed at authority and specifically the police. A quote attributed to Keith Richards was "I don't have a drug problem, I have a police problem".  So again there's those who are for me and those who are agin me the early adolescent dilemna when the child is first leaving home, rejected parents for friends and struggling to resolve in group and out group association.  Marijuana smokers are especially prone to conspiracy theories.  Ask any marijuana smoker about 9-11 and it's sure to be an adventure in some mix of fantasy and reality.
Cocaine seems more specifically paranoia associated with money.  The 'harder' the drug the more of the frontal lobe or humanity of an indivdual is lost. Cocaine addiction and psychopathy go hand in hand with sex and  money the 'pac man' pursuit of the addict.
In all these cases treating the addiction is the answer.  For most people removing the substance for a year or two allows the persons brain to restore especially if there is a process of mental "decontamination' removing them from the cult paranoid thinking that helps to perpetuate addiction. 12 step communities and religious and ethnic communities and families can counteract the paranoid gang like thinking that goes hand in had with the addiciton.  Dr. Rabbi Twerki's book Addictive Thinking is a marvellous treatise on the negative effects of addiction on thought.  Insight therapies have traditionally proved very unsuccessful with addicts and the development of group therapy and motivational therapy and 12 step faciltation therapies often coupled with spiritual psychiatry approaches is now considered the treatment of choice psychotherapeutically.
Given that addictions are anxiety avoidance techniques and addicts collectively have by nature an underlying anxiety disorder most of the insight therapies and essentially therapies that result in eureka and dynamic realization and change as a consequence of new learning don't work with addicts because change causes anxiety and promotes relapse.  Supportive therapies usually are beneficail in the first three months of therapy when a patient abstinent is detoxing. Anxiety provoking therapies, psychoanalytic, relationship etc are used carefully because of the learning impairment implicit with addiction.  Addicts have rarely been able to grasp quantum changes but can learn more of the same old same old in a clever way.  Historically they were once using therapists consciously or unconsciously like psychopaths do, to improve their game with no real intention of changing.  Therapists who aren't trained in addiction more commonly are 'enablers' and on the street are called the 'addict's bitch'.   Meanwhile the therapist is either feeling warm and fuzzy or thinking of how much money they are making.
Antipsychotic medications are beneficial in the first year of treatment of addicts.
Commonly therapeutically I may agree in part but not in whole with a paranoid so that I don't so easily become caught in their black and white reality.  For example I might say 'The CIA can be concerning" in response to the patient telling me he believes the CIA have planted a chip in his tooth. I certainly wouldn't disagree with him without proof.  I watch NCIS and Insecurity on television so I know what spy agencies are capable. I will focus my attention however on 'why you'.  And what can you do to effectively not be overwhelmed by this fear.
Finally I like to remember, especially when I have my own paranoid moments, that Jesus said, "Do not be afraid."  My minister psychiatrist friend and colleague likes to say, "That wasn't a suggestion. That's a command."