It is also used in small doses as an antiemetic drug.
It may cause involuntary movements of the face and limbs, lethargy, dry mouth, blurred vision, and dizziness.
It is also used in small doses as an antiemetic drug.
It may cause involuntary movements of the face and limbs, lethargy, dry mouth, blurred vision, and dizziness.
Diagnosis is usually made with audiometry (see hearing tests) or other hearing tests, and a caloric test.
Treatment with certain antihistamine drugs, such as cinnarizine, or with betahistine usually relieves the symptoms, although prochlorperazine may be given, either rectally or by injection, for severe attacks.
Ménière’s disease can also be treated by surgery to the inner ear if symptoms are not controlled by drugs.
If deafness eventually becomes total, the other symptoms usually disappear.... ménière’s disease
Most of these drugs act by blocking DOPAMINE receptors. As a result they can give rise to the extrapyramidal effects of PARKINSONISM and may also cause HYPERPROLACTINAEMIA.
Troublesome side-effects may require control by ANTICHOLINERGIC drugs. The main antipsychotic drugs are: (i) chlorpromazine, methotrimeprazine and promazine, characterised by pronounced sedative effects and a moderate anticholinergic and extrapyramidal e?ect; (ii) pericyazine, pipothiazine and thioridazine, which have moderate sedative effects and marked anticholinergic effects, but less extrapyramidal effects than the other groups; (iii) ?uphenazine, perphenazine, prochlorperazine, sulpiride and tri?uoperazine, which have fewer sedative effects and fewer anticholinergic effects, but more pronounced extrapyramidal effects.... neuroleptics
Uses Phenothiazines should be prescribed and used with care. The drugs di?er in predominant actions and side-effects; selection depends on the extent of sedation required and the susceptibility of the patient to extrapyramidal side-effects. The di?erences between the drugs, however, are less important than the variabilities in patients’ responses. Patients should not be prescribed more than one antipsychotic drug at a time. In the short term these therapeutically powerful drugs can be used to calm disturbed patients, whatever the underlying condition (which might have a physical or psychiatric basis). They also alleviate acute anxiety and some have antidepressant properties, while others worsen DEPRESSION (see also MENTAL ILLNESS).... phenothiazines
Causes The simplest cause of vertigo is some mechanical disturbance of the body affecting the ?uid in the internal ear; such as that produced by moving in a swing with the eyes shut, the motion of a boat causing sea-sickness, or a sudden fall. (See also MOTION (TRAVEL) SICKNESS.)
Another common positional variety is benign paroxysmal positional vertigo (BPPV) caused by sudden change in the position of the head; this causes small granular masses in the cupola of the posterior semicircular canal in the inner ear to be displaced. It may subside spontaneously within a few weeks but can recur. Sometimes altering the position of the head so as to facilitate return of the crystals to the cupola will stop the vertigo.
The cause which produces a severe and sudden giddiness is MENIÈRE’S DISEASE, a condition in which there is loss of function of the vestibular mechanism of the inner ear. An acute labyrinthitis – in?ammation of the labyrinth of the ear – may result from viral infection and produce a severe vertigo lasting 2–5 days. Because it often occurs in epidemics it is often called epidemic vertigo. Vertigo is sometimes produced by the removal of wax from the ear, or even by syringing out the ear. (See EAR, DISEASES OF.)
A severe upset in the gastrointestinal tract may cause vertigo. Refractive errors in the eyes, an attack of MIGRAINE, a mild attack of EPILEPSY, and gross diseases of the brain, such as tumours, are other causes acting more directly upon the central nervous system. Finally, giddiness may be due to some disorder of the circulation, for example, reduced blood supply to the brain produced by fainting, or by disease of the heart.
Treatment While the attack lasts, this requires the sufferer to lie down in a darkened, quiet room. SEDATIVES have most in?uence in diminishing giddiness when it is distressing. After the attack is over, the individual should be examined to establish the cause and, if necessary, to be given appropriate treatment.
Vertigo and nausea linked to Menière’s disease – or following surgery on the middle ear – can be hard to treat. HYOSCINE, ANTI HISTAMINE DRUGS and PHENOTHIAZINES – for example, prochlorperazine – are often e?ective in preventing and treating these disorders. Cinnarizine and betahistine have been marketed as e?ective drugs for Menière’s disease; for acute attacks, cyclizine or prochlorperazine given by intramuscular injection or rectally can be of value. Research in America is exploring the use of virtual-reality technology to change subjects’ visual perception of the outside world gradually during several 30-minute sessions, helping them to adjust to the abnormal sensations that occur during an attack. Early results are promising.... vertigo
Causes Vomiting is brought about by stimulation of this nervous centre, and in most cases this is e?ected through sensations derived from the stomach itself. Thus, of the drugs which cause vomiting, some act only after being absorbed into the blood and carried to the brain, although most are irritants to the mucous membrane of the stomach (see EMETICS); various diseases of the stomach, such as cancer, ulcer and food poisoning act in a similar way. Stimulation – not only of the nerves of the stomach, but also of those supplying other abdominal organs – produces vomiting; thus in obstruction of the bowels, peritonitis, gall-stone colic, renal colic, and even in some women during pregnancy, vomiting is a prominent symptom.
Severe emotional shock may cause vomiting, as may acute anxiety and unpleasant experiences such as seeing an accident, suffering severe pain or travel sickness.
Direct disturbance of the brain itself is a cause: for example, a blow on the head, a cerebral tumour, a cerebral abscess, meningitis. Nausea and vomiting are common symptoms that may arise from local disease of the gastrointestinal tract, but they are also associated with systemic illness – for example, DIABETES MELLITUS or kidney failure (see KIDNEYS, DISEASES OF) – and also with disturbances of labyrinthine function, such as motion sickness and acute labyrinthitis.
Treatment The cause of the vomiting must be sought and treatment directed towards this. Symptomatic treatment for vomiting can be dangerous since accurate diagnosis of the cause may be hindered. If antinauseant drug treatment is indicated, the choice of drug depends on the cause of the vomiting.
Granisetron and ondansetron are 5hydroxytryptamine (5HT3) antagonists valuable in the treatment of nausea and vomiting induced by cytotoxic CHEMOTHERAPY or RADIOTHERAPY and prevention and treatment of post-operative nausea and vomiting. Prochlorperazine is valuable in the treatment of severe nausea, vomiting, VERTIGO and disorders of the LABYRINTH of the EAR, although extrapyramidal symptoms may occur, particularly in children, elderly and debilitated patients.
Vomiting may occur after surgical operations and this is due to the combined effects of analgesics, anaesthetic agents and the psychological stress of operation. Various drugs can be used to prevent or stop post-operative vomiting.
Nausea and vomiting are common symptoms in pregnancy. Drugs are best avoided in this situation as they may damage the developing FETUS. Simple measures, such as the taking of food before getting up in the morning and reassurance, are often all that is necessary.... vomiting