Imipramine Health Dictionary

Imipramine: From 2 Different Sources


A well-established, relatively safe tricyclic antidepressant (see ANTIDEPRESSANT DRUGS) used to treat DEPRESSION; the drug does, however, have antimuscarinic and cardiac side-effects. It is also used to treat ENURESIS by an action distinct from its antidepressant e?ect.
Health Source: Medical Dictionary
Author: Health Dictionary
n. a drug administered by mouth to treat depression (see antidepressant) and, in children, bedwetting. Common side-effects include dry mouth, blurred vision, constipation, sweating, and rapid heartbeat.
Health Source: Oxford | Concise Colour Medical Dictionary
Author: Jonathan Law, Elizabeth Martin

Antidepressant Drugs

These widely used drugs include a range of different preparations which relieve DEPRESSION. All the antidepressants available at the time of writing are more or less equally e?ective. In studies where patients agree to take either antidepressants or identical dummy PLACEBO pills (without knowing which), at least two-thirds of those who receive antidepressants feel much better within three months, while fewer than one-third of those on placebos recover naturally in the same period. In general these drugs are useful for severe and moderate depression including postnatal illness; they are not e?ective in milder forms of depression although they may be tried for a short time if other therapies have failed.

The most widely prescribed type of antidepressants are the tricyclics, so-called because their molecular structure includes three rings. The other commonly used types are named after the actions they have on chemicals in the brain: the SELECTIVE SEROTONIN-REUPTAKE INHIBITORS (SSRIS) and the MONOAMINE OXIDASE INHIBITORS (MAOIS) – see also below. All types of antidepressant work in similar ways. Tricyclic antidepressants have cured depression in millions of people, but they can cause unpleasant side-effects, particularly in the ?rst couple of weeks. These include SEDATION, dry mouth, excessive sweating, CONSTIPATION, urinary problems, and impotence (inability to get an erection). Up to half of all people prescribed tricyclic drugs cannot tolerate the side-effects and stop treatment before their depression is properly treated. More seriously, tricyclics can upset the rhythm of the heart in susceptible people and should never be given in the presence of heart disease.

The SSRIs are newer, coming into wide use in the late 1980s. They increase the levels in the brain of the chemical messenger SEROTONIN, which is thought to be depleted in depression. Indeed, the SSRIs are as e?ective as tricyclics and, although they can cause nausea and excessive sweating at ?rst, they generally have fewer side-effects. Their main disadvantage, however, is that they cost much more than the most commonly used tricyclic, amitriptyline. On the other hand, they are more acceptable to many patients and they cause fewer drop-outs from treatment – up to a quarter rather than a half. The money saved by completed, successful treatment may outweigh the prescribing costs. SSRIs have been reported as associated with an increased risk of suicide.

Another group of antidepressants, the MAOIs, have been in use since the late 1950s.

They are stimulants, rather than sedatives, and are particularly helpful for people who are physically and mentally slowed by depression. They work well but have one big disadvantage – a dangerous interaction with certain foods and other drugs, causing a sudden and very dangerous increase in blood pressure. People taking them must carry an information card explaining the risk and listing the things that they should avoid. Because of this risk, MAOIs are not used much now, except when other treatments have failed. A new MAOI, moclobemide, which is less likely to interact and so cause high blood pressure, is now available.

LITHIUM CARBONATE is a powerful antidepressant used for intractable depression. It should be used under specialist supervision as the gap between an e?ective dose and a toxic one is narrow.

St John’s Wort is a popular herbal remedy which may be e?ective, but which is handicapped by di?erences of strength between di?erent preparations or batches. It can interact with a number of conventional drugs and so needs to be used cautiously and with advice.

In general, antidepressants work by restoring the balance of chemicals in the brain. Improved sleep and reduced anxiety are usually the ?rst signs of improvement, particularly among people taking the more sedative tricyclic drugs. Improvement in other symptoms follow, with the mood starting to lift after about two weeks of treatment. Most people feel well by three months, although a few residual symptoms, such as slowness in the mornings, may take longer to clear up. People taking antidepressants usually want to stop them as soon as they feel better; however, the risk of relapse is high for up to a year and most doctors recommend continuing the drugs for around 4–6 months after recovery, with gradual reduction of the dose after that.

Withdrawal reactions may occur including nausea, vomiting, headache, giddiness, panic or anxiety and restlessness. The drugs should be withdrawn gradually over about a month or longer (up to six months in those who have been on maintenance treatment).

A wide range of antidepressant drugs is described in the British National Formulary. Examples include:

Tricyclics: amitryptyline, imipramine, doxepin.

MAOIs: phenelzine, isocarboxazid.

SSRIs: citalopram, ?uoxetine, paraxtene. (Antidepressant drugs not in these three

groups include ?upenthixol, mertazapine and venlafaxine.)... antidepressant drugs

Tricyclic Antidepressants

A type of antidepressant drug.

Tricyclic antidepressants prevent neurotransmitters in the brain from being reabsorbed, thereby increasing their level.

Examples are amitriptyline, clomipramine, and imipramine.... tricyclic antidepressants

Depression

Depression is a word that is regularly misused. Most people experience days or weeks when they feel low and fed up (feelings that may recur), but generally they get over it without needing to seek medical help. This is not clinical depression, best de?ned as a collection of psychological symptoms including sadness; unhappy thoughts characterised by worry, poor self-image, self-blame, guilt and low self-con?dence; downbeat views on the future; and a feeling of hopelessness. Su?erers may consider suicide, and in severe depression may soon develop HALLUCINATIONS and DELUSIONS.

Doctors make the diagnosis of depression when they believe a patient to be ill with the latter condition, which may affect physical health and in some instances be life-threatening. This form of depression is common, with up to 15 per cent of the population suffering from it at any one time, while about 20 per cent of adults have ‘medical’ depression at some time during their lives – such that it is one of the most commonly presenting disorders in general practice. Women seem more liable to develop depression than men, with one in six of the former and one in nine of the latter seeking medical help.

Manic depression is a serious form of the disorder that recurs throughout life and is manifested by bouts of abnormal elation – the manic stage. Both the manic and depressive phases are commonly accompanied by psychotic symptoms such as delusions, hallucinations and a loss of sense of reality. This combination is sometimes termed a manic-depressive psychosis or bipolar affective disorder because of the illness’s division into two parts. Another psychiatric description is the catch-all term ‘affective disorder’.

Symptoms These vary with the illness’s severity. Anxiety and variable moods are the main symptoms in mild depression. The sufferer may cry without any reason or be unresponsive to relatives and friends. In its more severe form, depression presents with a loss of appetite, sleeping problems, lack of interest in and enjoyment of social activities, tiredness for no obvious reason, an indi?erence to sexual activity and a lack of concentration. The individual’s physical and mental activities slow down and he or she may contemplate suicide. Symptoms may vary during the 24 hours, being less troublesome during the latter part of the day and worse at night. Some people get depressed during the winter months, probably a consequence of the long hours of darkness: this disorder – SEASONAL AFFECTIVE DISORDER SYNDROME, or SADS – is thought to be more common in populations living in areas with long winters and limited daylight. Untreated, a person with depressive symptoms may steadily worsen, even withdrawing to bed for much of the time, and allowing his or her personal appearance, hygiene and environment to deteriorate. Children and adolescents may also suffer from depression and the disorder is not always recognised.

Causes A real depressive illness rarely has a single obvious cause, although sometimes the death of a close relative, loss of employment or a broken personal relationship may trigger a bout. Depression probably has a genetic background; for instance, manic depression seems to run in some families. Viral infections sometimes cause depression, and hormonal disorders – for example, HYPOTHYROIDISM or postnatal hormonal disturbances (postnatal depression) – will cause it. Di?cult family or social relations can contribute to the development of the disorder. Depression is believed to occur because of chemical changes in the transmission of signals in the nervous system, with a reduction in the neurochemicals that facilitate the passage of messages throughout the system.

Treatment This depends on the type and severity of the depression. These are three main forms. PSYCHOTHERAPY either on a one-to-one basis or as part of a group: this is valuable for those whose depression is the result of lifestyle or personality problems. Various types of psychotherapy are available. DRUG TREATMENT is the most common method and is particularly helpful for those with physical symptoms. ANTIDEPRESSANT DRUGS are divided into three main groups: TRICYCLIC ANTIDEPRESSANT DRUGS (amitriptyline, imipramine and dothiepin are examples); MONOAMINE OXIDASE INHIBITORS (MAOIS) (phenelzine, isocarboxazid and tranylcypromine are examples); and SELECTIVE SEROTONIN REUPTAKE INHIBITORS (SSRIS) (?uoxetine – well known as Prozac®, ?uvoxamine and paroxetine are examples). For manic depression, lithium carbonate is the main preventive drug and it is also used for persistent depression that fails to respond to other treatments. Long-term lithium treatment reduces the likelihood of relapse in about 80 per cent of manic depressives, but the margin between control and toxic side-effects is narrow, so the drug must be carefully supervised. Indeed, all drug treatment for depression needs regular monitoring as the substances have powerful chemical properties with consequential side-effects in some people. Furthermore, the nature of the illness means that some sufferers forget or do not want to take the medication. ELECTROCONVULSIVE THERAPY (ECT) If drug treatments fail, severely depressed patients may be considered for ECT. This treatment has been used for many years but is now only rarely recommended. Given under general anaesthetic, in appropriate circumstances, ECT is safe and e?ective and may even be life-saving, though temporary impairment of memory may occur. Because the treatment was often misused in the past, it still carries a reputation that worries patients and relatives; hence careful assessment and counselling are essential before use is recommended.

Some patients with depression – particularly those with manic depression or who are a danger to themselves or to the public, or who are suicidal – may need admission to hospital, or in severe cases to a secure unit, in order to initiate treatment. But as far as possible patients are treated in the community (see MENTAL ILLNESS).... depression

Narcolepsy

A condition in which uncontrollable episodes of sleep occur two or three times a day. It starts at any age and persists for life. The attacks, which usually last for 10–15 minutes, come on suddenly at times normally conducive to sleep, such as after a meal, or sitting in a bus, but they may occur when walking in the street. In due course, usually after some years, they are associated with cataplectic attacks (see CATAPLEXY), when for a few seconds there is sudden muscular weakness affecting the whole body. The cataplectic attacks can be controlled by the TRICYCLIC ANTIDEPRESSANT DRUGS, imipramine or clomipramine.

Familial narcolepsy is well recognised, and recently a near-100-per-cent association between narcolepsy and the histocompatability antigen HLA-DR2 (see HLA SYSTEM) has been discovered, which suggests that narcolepsy is an immunorelated disease. The Narcolepsy Association (UK) has been founded to help patients with this strange disorder.... narcolepsy

Nocturnal Enuresis

The involuntary passing of URINE during sleep. It is a condition predominantly of childhood, and usually genetically determined. Sometimes, however, it is a symptom of anxiety in a child, especially if there has been over-rigorous attempts at toilet-training or hostile or unloving behaviour by a parent. It can also be provoked by apparently unimportant changes in a child’s life – for example, moving house. In a small minority of cases it is due to some organic cause such as infection of the genitourinary tract.

The age at which a child achieves full control of bladder function varies considerably. Such control is sometimes achieved in the second year, but much more commonly not until 2–3 years old. Some children do not normally achieve such control until the fourth, or even ?fth, year, so that paediatricians are reluctant to make this diagnosis before a child is aged six.

The approach consists essentially of reassurance and ?rm but kindly and understanding training. In most cases the use of a ‘star chart’ and a buzzer alarm which wakens the child should he or she start passing urine is helpful. Where there are relationship or social problems, these need to be considered in treating the child. The few who have urinary infection or irritable bladders may respond to drug tretament.

Those who do not respond may be helped by DDAVP, an analogue of a pituitary hormone, which reduces the amount of urine produced overnight. It is licensed for use for three months at a time. Some children prefer to reserve it for occasions such as sleeping away from home. The antidepressant imipramine can help some children but has to be used cautiously because of side-effects.

For help, contact www.eric.org.uk... nocturnal enuresis

Illusion

A distorted sensation based on misinterpretation of a real stimulus (for example, a pen is seen as a dagger). It is differs from a hallucination, in which a perception occurs without any stimulus.Usually, illusions are brief and can be understood when explained. They may be due to tiredness or anxiety, to drugs, or to forms of brain damage. Delirium tremens is a classic inducer of illusions. imaging techniques Techniques that produce images of structures within the body. The most commonly used and simplest techniques are X-rays (to view dense structures such as bone) and contrast X-rays, in which a medium, such as barium, that is opaque to X-rays is introduced into the body. Contrast X-ray techniques include barium X-ray examinations (used to examine the oesophagus, the stomach and the small intestine); cholecystography (used to visualize the gallbladder and common bile duct); bronchography (to view the airways connecting the windpipe to the lungs); angiography and venography (to provide images of the blood vessels); intravenous urography (to visualize the kidneys and urinary tract); and ERCP (by which the pancreatic duct and biliary system are examined).

Many X-ray imaging techniques have been superseded by newer procedures. These include ultrasound scanning, MRI (magnetic resonance imaging), PET scanning, and radionuclide scanning. However, X-rays are used in CT scanning. Some of these techniques use computers to process the raw imaging data and produce the actual image. Others can produce images without a computer, although one may be used to enhance the image. imipramine A tricyclic antidepressant drug most commonly used as a longterm treatment for depression. Possible adverse effects include excessive sweating, blurred vision, dizziness, dry mouth, constipation, nausea, and, in older men, difficulty passing urine.... illusion

Antidepressant

n. a drug designed to alleviate the symptoms of *depression. Most antidepressants act by altering the availability of *serotonin and *noradrenaline in the brain; they are also likely to influence synaptic transmission regulation and postsynaptic conduction. There are four main classes of antidepressants. The selective serotonin reuptake inhibitors, such as fluoxetine, sertraline, escitalopram, and citalopram (see SSRI), are recommended as first-line treatment for depression and anxiety by current NICE guidelines. Their mode of action is entirely on serotonin. Side-effects include gastrointestinal problems and nausea. Tricyclic antidepressants, such as *imipramine, *doxepin, *lofepramine, *clomipramine, and *amitriptyline, are also widely used. They act on noradrenaline as well as serotonin, although most of them primarily have a noradrenergic action. They are also used in chronic pain management. Their side-effect profile varies from that of SSRIs; on the whole they have more *antimuscarinic effects and are more sedative. They are more dangerous in overdose than SSRIs and cause more weight gain. Other side-effects include postural hypotension. Serotonin and noradrenaline reuptake inhibitors), such as venlafaxine and duloxetine (see SNRI), are a common second-line choice in the treatment of depression and anxiety. Monoamine oxidase inhibitors (MAOIs), such as the reversible moclobemide and the irreversible phenelzine (see MAO inhibitor), are older antidepressants. They are now less used because of significant side-effects and interactions with other drugs. The irreversible MAOIs also require certain dietary restrictions. Antidepressants are not addictive, but depending on their half-life they show a varying prevalence of *discontinuation syndrome. Antidepressants have consistently been shown to be more effective than placebo. Their efficacy is lower in mild depression but moderate to good in moderate and severe depression. They are part of the gold-standard treatment for depression and anxiety.... antidepressant



Recent Searches