Paula Viñas
José de Felippe Junior

Existem inúmeros tipos de dor de cabeça, com as mais variadas causas. A que vamos descrever aqui são as causadas por prostaglandinas, que provocam vasodilatação, ocasionando forte dor na região da cabeça.

As prostaglandinas são produtos de metabolismo do ácido graxo. Toda vez que a enzima fosfolipase A2 for ativada, liberará um componente da membrana celular: o ácido aracdônico. O ácido aracdônico sofre ação da enzima COX 1 e 2, formando assim as prostaglandinas. Essa explicação está esquematizada seguir:

agentes físicos(trauma mecânico, radiação, calor, frio) químicos(substâncias irritantes, alcalis) biológicos (fungos, bactérias, vírus, protozoário)

                                                    ↓

fosfolipase A2 → membrana celular

↓

ácido aracdônico  

↓

ciclooxigenase (COX 1/ COX2)

 ↓

prostaglandina

A aspirina, age justamente nesse mecanismo de ação: ela bloqueia a enzima COX de forma não seletiva, impedindo que a prostaglandina se forme.

Salix alba L.

É quimicamente constituído de salicina que possui propriedades febrífugas, anestésica, anti – reumática sedativa e hemostatica. O Salix alba tem atividade antiinflamatória comparável com altas doses de ácido salicilico (aspirina). (Marz,R. et al., 2002).

Todas as plantas medicinais consideradas do grupo das metilxantinas, possuem a propriedade de estimular a vasoconstricção, revertendo assim o efeito das prostaglandinas que promovem a vasodilatação e consequentemente a dor de cabeça. São elas:

guaraná (Paulinia cupana)

erva mate (Ilex paraguariensis)

chá da Índia (Camellia sinensis L.)

Referência Bibliográfica:

Marz,R. ,et all. Willow bark extract – elfeets and effectiveners. Status of current knowledge regarding pharmacology toxicology and clinical aspects. Med Wochenschr. 2002;152;(15-16):354-359

Outras plantas

Alternative therapies in the treatment of headache in childhood

Neurol;20(1):9-14, 2005 Jan-Mar. Termine C; Ginevra OF; D'Arrigo S; Rossi M; Lanzi G

Resumo: In recent years, it has become common practice, in the treatment of headache, to use alternative methods, both alone and in association with drug therapies. Alternative therapies would appear to be more indicated in certain subjects: patients opposed to pharmacological treatments, those showing low tolerance of drugs or with a history of drug abuse, and those presenting medical contraindications or poor response to certain drugs. Numerous studies of alternative therapies have been published and here we review the literature data on the topic, considering in particular the accuracy of the various study methods in evaluating the effectiveness of the different therapies and their specificity for the different forms of headache. Specialists involved in the assessment and care of headache patients should strive to increase their knowledge of alternative therapies, so as to be better equipped to guide patients towards safe, economical and potentially effective treatments, rather than useless, costly or dangerous ones.

Alternative therapies for tension-type headache.

Curr Pain Headache Rep;8(6):484-8, 2004 Dec. Lenaerts ME

Resumo: Treatment of tension-type headache remains very challenging. In addition to conventional therapies, alternative methods such as physical therapy, acupuncture, and botulinum toxin have been studied. In this article, recent literature is reviewed and discussed and challenges for the evaluation of these approaches are considered. Although the clinical evidence is still incomplete, certain treatments are promising and the active ongoing research hopefully will soon yield more answers. Of note, the specific issue of psychologic therapy is dealt with elsewhere in this issue.

Feverfew for headaches.

Consum Rep;70(1):49, 2005 Jan.

Trattamento dei disturbi neurovegetativi della donna in menopausa con un preparato fitoterapico..

Minerva Ginecol;50(5):207-11, 1998 May. De Leo V; Lanzetta D; Cazzavacca R; Morgante G

Resumo: BACKGROUND: Menopausal symptoms include hot flushes, insomnia, nocturnal sweating, dizziness, headaches and palpitations. These symptoms reflect adaptation of the body to estrogen deprivation which affects various central neurotransmitters. METHODS: In this study, the efficacy has been tested of a plant product based on extracts of the leaves of Salvia officinalis (sage) and Medicago sativa (alfalfa) in the treatment of hot flushes in 30 menopausal women with these symptoms. RESULTS: Hot flushes and night sweating completely disappeared in 20 women: four women showed good improvement and the other six showed a reduction in symptoms. GnRH and TRH tests were performed in 8 women to evaluate TSH and Prl responses before and after 3 months of therapy. The plants product induced a significant increase in Prl and TSH response to TRH. Basal levels of estradiol, LH, FSH, Prl and TSH were unchanged. CONCLUSIONS: The product seams to have a central slight antidopaminergic action without side effects and is an effective agent in the treatment of menopausal symptoms.

Studies on the efficacy of unconventional therapies. Problems and designs.

Arzneimittelforschung;45(1):88-92, 1995 Jan Gaus W; Högel J.

Resumo: Many unconventional therapies (e.g. dietary, phytotherapy, acupuncture, homeopathy) are well known and often applied, but their efficacy has hardly been proven. New trial designs and study components must be found to meet the specific demands of the particular unconventional therapy on one hand and keep the high methodological standard of controlled clinical trials on the other hand. Biometricians and unconventional therapists are challenged to develop such designs. Typical problems in designing studies of unconventional therapies include that placebo is not possible, therapies cannot be masked, outcome variables are not reliable, therapy is highly individualized, and studies on the efficacy of soft therapies require many patients and long treatment periods. Studies with unconventional therapies should be performed by practitioners (because they use these therapies), but this leads to further problems. Some solutions are given in examples: A study is described investigating the herbal remedy Kava-Kava for patients in the state of anxiety, tension and restlessness; a study on classical homeopathy for chronical headaches is specified; some designs for dietary studies in patients with rheumatoid arthritis are compared. A design called [quot ]cross-allocation of patients to two treatments with randomization option[quot ] and the [quot ]N-of-1 design[quot ], also called [quot ]single case design[quot ] are described and discussed. The [quot ]change-to-open-label design[quot ] could be useful to investigate soft and natural therapies which require studies with many patients and long-term treatment.

Headache treatments by native peoples of the Ecuadorian Amazon: a preliminary cross-disciplinary assessment.

J Ethnopharmacol;36(3):193-206, 1992 Jun. Russo EB

Resumo: Headache, specifically migraine, is an extremely frequent and debilitating syndrome with worldwide prevalence, including indigenous cultures of Amazonia. This paper considers headache as perceived within the medical philosophy of 5 Indian tribes of the Ecuadorian Amazon Basin. Their ethnobotanical treatments for headache are examined, along with the limited available biochemical assay data. This information is analyzed by means of an Ethnopharmacology Rating Scale. Suggestions are offered as to methods of biochemical analysis that may be fruitful in assessment of potential clinical headache remedies. Key among these is the screening of ethnobotanical samples for serotonin receptor activity. The potential may exist for the discovery of more effective, less toxic headache drugs, as well as for the development of a new industry for the local economy that could promote conservation of an endangered ecosystem.

Inhibition of platelet aggregation and 5-HT release by extracts of Australian plants used traditionally as headache treatments.

Eur J Pharm Sci;9(4):355-63, 2000 Feb. Rogers KL; Grice ID; Griffiths LR

Resumo: To identify potential migraine therapeutics, extracts of eighteen plants were screened to detect plant constituents affecting ADP induced platelet aggregation and [14C]5-hydroxytryptamine (5-HT) release. Extracts of the seven plants exhibiting significant inhibition of platelet function were reanalysed in the presence of polyvinyl pyrrolidone (PVP) to remove polyphenolic tannins that precipitate proteins. Two of these extracts no longer exhibited inhibition of platelet activity after removal of tannins. However, extracts of Crataegus monogyna, Ipomoea pes-caprae, Eremophila freelingii, Eremophila longifolia, and Asteromyrtus symphyocarpa still potently inhibited ADP induced human platelet [14C]5-HT release in vitro, with levels ranging from 62 to 95% inhibition. I. pes-caprae, and C. monogyna also caused significant inhibition of ADP induced platelet aggregation. All of these plants have been previously used as traditional headache treatments, except for C. monogyna which is used primarily for protective effects on the cardiovascular system. Further studies elucidating the compounds that are responsible for these anti-platelet effects are needed to determine their exact mechanism of action.

Screening of Zulu medicinal plants for prostaglandin-synthesis inhibitors.

J Ethnopharmacol;52(2):95-100, 1996 Jun. Jäger AK; Hutchings A; van Staden J

Resumo: Aqueous and ethanolic extracts of 39 plants used in traditional Zulu medicine to treat headache or inflammatory diseases were screened for prostaglandin-synthesis inhibitors. Extracts were tested in an in vitro assay for cyclooxygenase inhibitors. In general, ethanolic extracts caused higher inhibition than aqueous extracts. Two-thirds of the plants screened had high inhibitory activity. The highest inhibition was obtained with ethanolic extracts of Bidens pilosa, Eucomis autumnalis, Harpephyllum caffrum, Helichrysum nudifolium, Leonotis intermedia, L. leonorus, Ocotea bullata, Rumex saggitatus, Solanum mauritianum, Synadenium cupulare and Trichilia dregeana.

Una visión transcultural de la patología neurológica y mental en una comunidad maya tzeltal de los Altos de Chiapas

Rev Neurol;24(131):848-54, 1996 Jul. Carod FJ; Vázquez-Cabrera C

Resumo: OBJECTIVES. This anthropological study forms part of field-work undertaken in Mahosik, a Tzeltal Maya community of 250 inhabitants in the Altos de Chiapas, to obtain insight into the neurological and psychosomatic pathology in an ethnic and cultural setting different to ours. MATERIAL AND METHOD. Accompanied by a Tzeltal translator we interviewed various witch-doctors and faith healers of the Tzeltal Maya tribe to find out their ideas about neurological and mental diseases and the treatments used. RESULTS. Headache or [quot ]k'ux jolol' is the fourth most common cause of consultation after acute respiratory and gastrointestinal disorders and fevers. To relieve it, the boiled leaves of the bush [quot ]payté' ([quot ]Tagetes neisonii') are used as a medicinal bath. Migraine, [quot ]yaxti-wanjol chawaj' is treated with the raw, crushed roots of the herbs [quot ]chopak pox' and [quot ]bakte pox' together with the practice of cutting the patient with a piece of glass in the temporal region, deep enough to make him bleed. Epilepsy or [quot ]tub tub ikal' is caused by an abuse suffered by the animal spirit which accompanies the individual, after a fight between the animal-companions or spirits which serve the forces of Good and Evil. The person with chronic crises is considered a witch. Depression or [quot ]melotan' is fairly common. This is treated with camomile tea containing an orange and a lime leaf. [quot ]Xiwel' or fear is one of the commonest psychosomatic disorders. The faith-healer has to return the lost spirit to its owner in a ceremony involving prayer, alcohol and the sacrifice of a fowl. Psychosis or [quot ]jowijel' may be due to alcohol, dog bite or witch craft and has no cure. Madness [quot ]chawaj' is caused by bewitchment during a nightmare. It is treated with the sap of [quot ]viborana' mixed with wild beans.

Effect of peppermint and eucalyptus oil preparations on neurophysiological and experimental algesimetric headache parameters .

Cephalalgia;14(3):228-34; discussion 182, 1994 Jun Göbel H; Schmidt G; Soyka D

Resumo: The effects of peppermint oil and eucalyptus oil preparations on neurophysiological, psychological and experimental algesimetric parameters were investigated in 32 healthy subjects in a double-blind, placebo-controlled, randomized cross-over design. Four different test preparations were applied to large areas of the forehead and temples using a small sponge and their effect was evaluated by comparing baseline and treatment measure. The combination of peppermint oil, eucalyptus oil and ethanol increased cognitive performance and had a muscle-relaxing and mentally relaxing effect, but had little influence on pain sensitivity. A significant analgesic effect with a reduction in sensitivity to headache was produced by a combination of peppermint oil and ethanol. The essential plant oil preparations often used in empiric medicine can thus be shown by laboratory tests to exert significant effects on mechanisms associated with the pathophysiology of headache.