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Query: UMLS:C0344232 (blurred vision)
 2,072 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Scopolamine is the most effective single drug for the prophylaxis and treatment of motion sickness. However, oral or injected scopolamine displays a comparatively short duration of action (5-6 hours), and leads to deleterious side effects on autonomic and central nervous system cholinergic functions. The transdermal scopolamine system was designed to reduce these problems, but while it does deliver scopolamine over a prolonged time period (72 h), deleterious side effects are also produced. Transdermal scopolamine provides significant motion sickness protection, similar in extent to that provided by oral scopolamine or dimenhydrinate. Its autonomic nervous system effects comprise reduced salivation, bradycardia, and blurred vision due to reduced visual accommodation. The visual problems increase following repeated patch applications, with hypermetropic ("long sighted") individuals particularly at risk. Central nervous system effects comprise reduced memory for new information, impaired attention, and lowered feelings of alertness. Variation in response to transdermal scopolamine has also been reported, both between individuals, and between different patch applications on the same individual.
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PMID:Transdermal scopolamine: a review of its effects upon motion sickness, psychological performance, and physiological functioning. 264 72

Scopolamine and placebo transdermal patches were applied on alternating days to 12 normal volunteer subjects. Psychological performance tasks, physiological assessments, a subjective feeling state questionnaire, and a sleep questionnaire were completed each day. Transdermal scopolamine produced significant decrements in memory task performance, daytime feelings of alertness, ease of waking, and alertness following waking, while resting heart rates were lowered. Significant drug x patch number interaction effects were present with memory for new information, letter cancellation omission errors, rapid visual information processing reaction time, and self-rated ease of getting to sleep, but there was no consistent pattern to the changes following successive patches. Visual problems (blurred vision, longer visual near point) increased following successive scopolamine patches, but the changes in task performance were not related to these visual changes.
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PMID:Transdermal scopolamine: effects of single and repeated patches upon psychological task performance. 362 92

Three placebo-controlled double-blind studies in healthy volunteers were performed to reveal the psychophysiological effects of scopolamine, ephedrine and their combination. Single intravenous dose of scopolamine 6 micrograms/kg (scopolamine hydrobromide 7.4 micrograms/kg) impaired various psychomotor functions both subjectively and objectively. It caused sedation, impairment of coordinative and reactive skills, visual disturbances and impairment of shortterm memory. Oral scopolamine hydrobromide in single doses of 0.3 mg and 0.9 mg, or 0.9 mg b.d. for 3 days, had few effects. A slight impairment of shortterm memory and a decrease in the flicker fusion threshold were seen. The visual nearpoint and pupil diameter were increased and some subjects reported blurred vision and dizziness during treatment with scopolamine 0.9 mg b.d. Scopolamine showed clear cardiovascular effects in all studies: it decreased heart rate and systolic blood pressure. Ephedrine alone and in combination with scopolamine had no deleterious effects. On the contrary, it antagonized the scopolamine-induced impairment in the flicker fusion test and the decrease in blood pressure and heart rate. In sufficient doses scopolamine impairs various psychomotor and cognitive skills. An oral dose of scopolamine hydrobromide 0.9 mg on average has few effects, although they may be very striking in certain individuals. To avoid unwanted effects and diminution in performance by scopolamine, doses less than 0.9 mg should be used.
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PMID:Psychomotor, physiological and cognitive effects of scopolamine and ephedrine in healthy man. 687 37

Patients with acquired forms of nystagmus may suffer from oscillopsia and blurred vision; abolishing or reducing nystagmus ameliorates these symptoms. Ideally, treatment of nystagmus should be directed against the pathophysiologic mechanism responsible. Identification of nystagmus pattern is important in directing therapy and occasionally requires electronic eye movement recording for precise characterization. Patients with acquired pendular nystagmus, particularly those with multiple sclerosis, often benefit from gabapentin, a drug with few side effects. Scopolamine, clonazepam, and valproate are also useful in some patients. A new drug, memantine, was effective in treating pendular nystagmus in one study, but it has not yet been approved for use in the United States. Periodic alternating nystagmus usually responds to baclofen. Central vestibular nystagmus, including downbeating and upbeating forms, can be treated with baclofen or clonazepam. In some patients, treatment of an underlying condition, such as periodic ataxia, Whipple's disease, and Chiari malformation, abolishes nystagmus and improves vision. If pharmacologic therapy fails, optical devices can be considered in selected patients. Injections of botulinum toxin and surgery to weaken extraocular muscles are prone to induce diplopia and may precipitate plastic-adaptive ocular motor changes that eventually negate the beneficial effect.
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PMID:Acquired Nystagmus. 1109 97

Hyoscine-N-butylbromide (Buscopan, Boehringer Ingelheim) is a widely used antispasmodic in radiological practice. There seems to be no consensus as to best practice within radiology regarding the precautions that need to be taken when prescribing Buscopan. We have performed a thorough review of the available literature and make the following recommendations to those administering Buscopan: (1) enquire whether there is an allergic history; (2) ensure patient literature warns that "in the rare event that following the examination you develop painful, blurred vision in one or both eyes, you must attend hospital immediately for assessment"; (3) warn patients to expect blurred vision and not to drive until this has worn off; (4) remind clinicians that special consideration needs to be given as to the method of investigating patients with cardiac instability, such as those recently admitted with acute coronary syndrome, recurrent cardiac pain at rest, uncontrolled left ventricular failure and recent ventricular arrhythmias.
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PMID:Precautions to be taken by radiologists and radiographers when prescribing hyoscine-N-butylbromide. 1855 31

Scopolamine hydrobromide (hyoscine) is an antimuscarinic drug which is primarily used in the prophylaxis and treatment of motion sickness and as a premedication to dry bronchial and salivary secretions. In acute overdosage, the main clinical problem is central nervous system (CNS) depression. In Australia, tablets containing scopolamine hydrobromide 0.3 mg are available over the counter in packs of ten. The recommended dose for adults is one to two tablets as a single dose, repeated four to six hours later, if required. The maximum dose stated on the pack is four tablets over a 24-hour period with a caution regarding drowsiness and blurred vision. We describe a patient who presented with symptoms of anticholinergic syndrome secondary to an unintentional overdose of scopolamine. Whilst at work, the patient noticed that he had forgotten his prescribed medication, domperidone, at home; a friend gave him some travel sickness medication which contained scopolamine for relief of nausea. On a previous occasion, he had experienced a similar, less severe reaction with another anticholinergic agent, loperamide. This report highlights the need to consider nonprescription products, ie, over the counter medications, herbal/nutritional supplements as causes of anticholinergic syndrome when a patient presents with symptoms suggestive of this diagnosis.
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PMID:Anticholinergic syndrome following an unintentional overdose of scopolamine. 1977 13

Black henbane (BH) or Hyoscyamus niger, has been used as a medicine since last centuries and has been described in all traditional medicines. It applies as a herbal medicine, but may induce intoxication accidentally or intentionally. All part of BH including leaves, seeds and roots contain some alkaloids such as Hyoscyamine, Atropine, Tropane and Scopolamine. BH has pharmacological effects like bronchodilating, antisecretory, urinary bladder relaxant, spasmolytic, hypnotic, hallucinogenic, pupil dilating, sedative and anti-diarrheal properties. Clinical manifestations of acute BH poisoning are very wide which include mydriasis, tachycardia, arrhythmia, agitation, convulsion and coma, dry mouth, thirst, slurred speech, difficulty speaking, dysphagia, warm flushed skin, pyrexia, nausea, vomiting, headache, blurred vision and photophobia, urinary retention, distension of the bladder, drowsiness, hyper reflexia, auditory, visual or tactile hallucinations, confusion, disorientation, delirium, aggressiveness, and combative behavior. The main treatment of BH intoxicated patients is supportive therapies including gastric emptying (not by Ipecac), administration of activated charcoal and benzodiazepines. Health care providers and physicians particularly emergency physicians and clinical toxicologists should know the nature, medical uses, clinical features, diagnosis and management of BH poisoning.
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PMID:Black henbane and its toxicity - a descriptive review. 2538 92