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Query: UMLS:C0030193 (pain)
 261,466 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The mode of action of some classical and newer drugs used in the preventive interval treatment of migraine is discussed in the light of a modern theory of the pathogenesis of migraine headache. This headache is produced when two elements--a passive distension of the extracranial arteries and a lowering of the pain threshold of the receptors situated in the walls of the affected vessels--are present simultaneously. The main humoral factors involved in this phenomenon are plasma-kinins, serotonin and--to a lesser degree--histamine. The role played by serotonin which is released by the blood platelets at the onset of the attack is twofold: on the one hand, free serotonin increases the permeability of the capillaries, favouring transudation of plasmakinins, and lowers the pain threshold, while on the other hand, its increased excretion causes a secondary reduction in its plasma concentration, promoting hypotonicity of the extracranial vessels. Among the substances used for prophylactic interval treatment, some, such as dihydroergotamine, clonidine and the beta-blocking agents have a purely vascular site of action, maintaining--by various mechanisms--the tone of the extracranial arteries and thus reducing their lability. Methysergide and pizotifene have a chiefly indirect effect on the vessels, by potentiating the effect of catecholamines or helping to maintain free serotonin at a certain level. They act primarily against the humoral elements responsible for lowering the pain threshold: methysergide by inhibiting the release and blocking the effects of serotonin, by countering the potentiating effect of serotonin on the pain induced by plasmakinins and by inhibiting histamine release; pizotifene by inhibiting the release and blocking the effects of histamine, by blocking the effects of serotonin and by slightly inhibiting the peripheral effects of plasmakinins. Thus, the multifactorial pathogenesis of migraine helps to explain the effectiveness against migraine of substances possessing the most varied pharmacodynamic profiles.
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PMID:[Mechanism of action of drugs currently used in the prevention of migraine]. 5 25

The headache phase of migraine may develop as the result of an abnormal interaction (and perhaps an abnormal release) of vasoactive neurotransmitters from terminals of the trigeminal nerve with large intracranial and extracranial blood-vessels. These blood-vessels, which dilate during the headache phase of migraine, are thought to receive axonal projections from all three divisions of the trigeminal nerve. Substance P, a potent vasodilating peptide, seems to be released from trigeminal nerve endings in response to nervous stimulation and is involved in the transmission of painful stimuli within the periphery. The vasoactive molecule serotonin, implicated in the pathogenesis of migraine, coexists with substance P in some terminals of the central nervous system and is present within the trigeminal ganglia. Within this nerve serotonin may modulate the function of primary sensory neurons. The abnormal release of substance P or as yet unidentified peptides or other transmitters from the fifth cranial nerve may explain both the hemicranial pain and the vasodilation which are characteristic of the headache of migraine.
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PMID:Neurotransmitters and the fifth cranial nerve: is there a relation to the headache phase of migraine? 9 Sep 71

A course of 10 daily acupuncture treatments was given to 200 patients who suffered from chronic pain syndromes of at least one year duration and the result assessed at the end of the course of treatment and after an interval of at least 2 months. Treatments were individualized using needling of body loci distally and near the site of pain, and ear acupuncture. In 38 patients suffering from chronic headaches, including 13 cases of migraine-type headache, 81% reported an improvement in their condition, but only one patient was pain free for the 2-month observation period. In 162 patients with other chronic pain problems, 99 or 61% were improved or pain free at the end of treatment; in 69 of these a worthwhile degree of improvement persisted over the observation period of 2 months. Thirteen percent of all patients did not respond to acupuncture and in 26% the response was considered as transient only. Daily treatments are not more effective than weekly or biweekly treatments. Pain in the neck and shoulder region, in the knee and low back pain responded to acupuncture with prolonged improvement in over 50% of the patients treated. Facial pain syndromes and pain in the region of the trunk were least responsive and only 3 of 11 patients with post-herpetic neuralgia reported still having less pain after 2 months. Needling of effective loci and particularly ear needling often causes an instantaneous reduction or disappearance of pain; the speed of this response can only be explained by a mechanism within the nervous system. Based on our experience acupuncture represents a useful therapeutic modality in the management of pain.
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PMID:Acupuncture in chronic pain. 13 11

Monoamines are involved in the central nervous assimilation and modulation of the pain flow. According to a personal hypothesis, a disorder of this biochemical control (in particular a precariousness of brain 5-hydroxytryptamine turnover), is the basic mechanism of some painful conditions, such as migraine and other essential headaches. Acute (infusion) and chronic (ingestion) administration of tryptophan to migraine-headache sufferers improved the clinical course significantly in respect to placebo. Few patients with untractable pain from disseminated cancer received daily infusion of tryptophan and ingested a few gr of this amnioacid: improvement of pain and reduction of morphine necessity was observed. Parachlorophenylalanine chronic administration in migraine-headache sufferers lowered the pain threshold so far as to provoke (in 20% of cases) spontaneous pains in the trunk, legs and arms. This systemic pain syndrome was promptly reversible by discontinuing the treatment. Spontaneous pain syndrome was not reported by others in the healthy subject; this suggests an apparent vulnerability of 5HT turnover in essential headaches.
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PMID:5-Hydroxytryptamine and pain modulation in man: a clinical pharmacological approach with tryptophan and parachlorophenylalanine. 14 17

A group of 47 elderly patients with various ailments and aged between 66 and 99 years were treated with tiapride: very good results were obtained in 7 cases of severe buccofacial dyskinesia, though the dosage had to go as high as 800 mg/day; results were excellent in 2 cases, good in 9, moderate in 5, and nil in 3 out of 19 patients with agitated states; overall results were good (1 failure) in 8 cases of alcoholism (4 acute and 4 chronic); 8 good results and 4 failures were noted in 12 patients with either cancer pain, or pain following zoster or due to arthrosis or migraine. The product was very well-tolerated by these elderly patients.
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PMID:[Therapeutic advances in geriatry. A report on 47 cases (author's transl)]. 22 63

The cerebrovascular concomitants of migraine, initial vasoconstrictriction succeeded by vasodilatation, have long been considered the primary event in the pathogenesis of headache. In recent years, certain physicochemical concomitants of the attack have been identified, all involving blood platelets: these include hyperaggregability, decrease 5-hydroxytryptamine concentration and decreased monoamine oxidase activity. These changes may represent the response to a circulating humoral agent, deriving perhaps from the pulmonary vascular bed. The agent may not only bring about nonspecific damage of the kind described but be responsible for the cerebrovascular changes and stimulation of pain receptors characteristic of the disease. This circulating humoral agent may belong to the prostaglandin family.
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PMID:Cerebrovascular changes in migraine: secondary manifestations of a circulating humoral agent? 29 Jul 40

Facial neuralgia appears in a variety of forms which have different fundamental pathophysiological mechanisms. Of decisive importance are neuralgias with sensitive trigeminal, intermediate (sensory root), glossopharyngeal and vagus nerves which are caused by functional disturbances or damage to the nerve. In addition, projected or referred pain occurs in intracranial and cervical affections. A vascular origin may be assumed for Horton's neuralgia. This periodic paroxysmal and unilateral facial neuralgia is related to migraine. Serotonin, histamine and plasma kinin may be important eliciting factors; the concomitant symptoms of lachyrmation and rhinorrhea, reddening of the eyes and the face and a transitory Horner's syndrome suggest participation of the sympathetic and parasympathetic systems. Consideration of the previously known pathophysiological mechanisms permits a differentiated therapy for the various facial neuralgias.
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PMID:[Pathophysiology of facial neuralgia (authors' transl)]. 30 39

The efficacy of cervical manipulation for migraine was evaluated. In a six-month trial, 85 volunteers suffering from migraine were randomly allocated to three treatment groups. One group received cervical manipulation performed by a medical practitioner or by a physiotherapist, another received cervical manipulation performed by a chiropractor, while the control group received mobilization performed by a medical practitioner or by a physiotherapist. For the whole sample, migraine symptoms were significantly reduced. No difference in outcome was found between those who received cervical manipulation, performed by chiropractor or orthodox therapist, and those who received the control treatment. Chiropractic treatment was no more effective than the other two treatments in reducing frequency, duration or induced disability of migraine attacks, but chiropractic patients did report a greater reduction in pain associated with their attacks.
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PMID:A controlled trial of cervical manipulation of migraine. 37 35

A survey of the literature is presented in two areas of biofeedback treatment for headache--muscle contraction and migraine--and a variety of miscellaneous pain syndromes. The studies done to date are characterized largely by lack of proper no-treatment or placebo control groups, by confounding biofeedback with a variety of other strategies, or by sample sizes too small to afford any reasonable conclusions about efficacy. There is some evidence that biofeedback works better for muscle contraction headache than false feedback, but it also appears that biofeedback is no more effective than relaxation training. The application of biofeedback to migraine or other pain syndromes remains of unproven value. Investigators seldom attempt to relate empirically their interventions to hypothetical models of pain mechanisms. The potential influence of extraneous factors linked to the therapeutic situation is pervasive in these studies, but examination of their specific roles in symptom reduction is largely missing. Some variables are listed which need to be examined and which may contribute to the alleviation of pain with much less expenditure of clinical resources than that demanded by biofeedback. Perhaps the main contribution of biofeedback has been to highlight such extraneous variables in the pain treatment setting.
Pain 1979 Dec
PMID:Biofeedback therapy for headache and other pain: an evaluative review. 39 8

Sixteen diagnosed functional headache patients treated with biofeedback techniques of frontalis EMG feedback and/or peripheral temperature feedback, with an average headache history of 18.2 years, were evaluated at an average interval of 37 weeks posttreatment. On the average, patients showed further improvement in their headache status as measured by average daily headache pain scores in contrast with termination values. Data were obtained via structured interviews conducted by an individual not involved in patient's treatment. Patients on the average showed declines in frontalis EMG during the follow-up sessions, but not increases in temperature as had been expected. The unclear role played by increasing peripheral temperature in follow-up of migraine patients is discussed.
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PMID:Clinical follow-up: treatment and outcome of functional headache patients treated with biofeedback. 42 18


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