Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0018681 (headache)
 56,091 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A detailed presentation of 15 case-histories of subjects of both sexes, drawn from all decennies of life from the first to the eight, suggesting a syndrome originated from a possible GABA deficiency, is carefully made. Such syndrome is believed to be characterized by basic depressive state, loss of the habit of stretching oneself, sleep disorders, mostly with early morning awakening, constipation and nuchal headache. The above symptoms have been associated to a deficiency of GABA after noting the very speed recovery after administration of N-dipropylacetic acid, an inhibitor of GABA transaminase.
 ...
PMID:A syndrome from a possible GABA deficiency. Clinical-therapeutic report on 15 cases. 35 28

Thirty patients with persistent chronic daily headache, unresponsive to various combinations of pharmacological and nonpharmacological treatment were selected for an open label study using divalproex sodium. All patients had normal liver function tests. After a baseline observation period of 1 month, patients were given divalproex sodium 1000 to 2000 mg per day, for a period of 3 months. Blood valproic acid levels were kept between 75 and 100 mcg/ml. Liver function studies and blood ammonia levels were obtained periodically. Based on weekly headache index, headache-free days, dysfunctional days and patients' general well-being rating and physicians' global assessment, two thirds of the patients improved significantly. The common side effects included weight gain, tremor, hair loss and nausea. Liver functions were unaffected by treatment. The possible mechanism of action of valproate in headache is discussed. Valproate appears to be a worthwhile addition to the prophylactic treatment of chronic recurrent headache.
Headache 1991 Feb
PMID:Valproate in the treatment of persistent chronic daily headache. An open label study. 203 76

3 parenteral progestogens (medroxyprogesterone acetate, northisterone enanthate, and dehydroxyprogesterone acetophenide with estradiol enanthate, DPA) were studied in 907 women during 14,958 cycles over a 10-year period. The findings are summarized in 9 diagrams. The frequency of the principal side effects - intermenstrual bleeding, amenorrhea, headache, dizziness and nervousness - varied with the different substances. Intermenstrual bleeding and amenorrhea were least serious using DPA. When the injections were administered at the appropriate intervals, the drugs were effective and no pregnancies occurred. After suspending the treatment, the menstrual pattern returned to normal and the endometrium was fully regenerated. To date no fetal abnormalities have been reported after discontinuing the treatment.
 ...
PMID:[Injectable contraceptives. 10 years' clinical experience]. 427 10

The efficacy of valproic acid in the treatment of intractable chronic daily headache, unresponsive to traditional prophylactic medications, was examined prospectively in 16 patients. Dosage of the medication was adjusted to maintain serum valproic acid levels between 50 and 100 micrograms/mL, provided there were no significant side effects at that level. Valproic acid prophylaxis was of some benefit in only 2 of 16 patients. One of these two patients discontinued therapy due to side effects. Eight of the 16 patients reported side effects which included nausea, diarrhea, anorexia, lethargy, sleepiness, confusion, blurred vision, and decreased libido. In conclusion, valproic acid was not effective in controlling chronic daily headache in the majority of patients in whom conventional therapy had failed, and 50% of patients reported side effects. There is a significant disparity in the reported efficacy of this drug in treating chronic daily headache. This disparity is most likely due to the poorly-defined nature of this variety of headache. It is, therefore, recommended that more stringent definition of this disorder be developed before therapeutic regimens are evaluated.
Headache 1995 Oct
PMID:Valproic acid treatment of chronic daily headache. 853 Feb 78

1. The GABA transaminase inhibitor and activator of glutamic acid decarboxylase, valproic acid is being used for the treatment of migraine. Its mechanism of action is unknown. We tested the effects of sodium valproate and GABAA-agonist muscimol on dural plasma protein ([125I]-bovine serum albumin) extravasation evoked by either unilateral trigeminal ganglion stimulation (0.6 mA, 5 ms, 5 Hz, 5 min) or substance P (SP) administration (1 nmol kg-1,i.v.) in anaesthetized Sprague-Dawley rats. 2. Intraperitoneal (i.p.) injection of sodium valproate or muscimol, but not baclofen (< or = 10 mg kg-1, i.p.) dose-dependently reduced dural plasma protein extravasation caused either by electrical trigeminal stimulation (ED50: 6.6 +/- 1.4 mg kg-1, i.p., and 58 +/- 18 micrograms kg-1, i.p. for valproate or muscimol, respectively) or by intravenous substance P administration (ED50: 3.2 +/- 1.4 mg kg-1, i.p. and 385 +/- 190 micrograms kg-1, i.p. for valproate or muscimol, respectively). 3. Valproate (6.6 mg kg-1, i.p.) or muscimol (58 micrograms kg-1, i.p.) had no effect on mean arterial blood pressure or heart rate when measured for 30 min after i.p. administration. 4. The GABAA-antagonist bicuculline (0.01 mg kg-1, i.p.) completely reversed the effect of valproate and muscimol on plasma extravasation following electrical stimulation or substance P administration, whereas the GABAB-receptor antagonist, phaclofen (0.01-1 mg kg-1, i.p.) did not. Bicuculline or phaclofen, given alone, did not alter the plasma extravasation response after either electrical stimulation or SP administration. 5. Valproate decreased plasma extravasation following substance P administration in adult animals, neonatally treated with capsaicin by a bicuculline-reversible mechanism. This suggests that GABAA receptors are not found primarily on those afferent neurones or fibres which are sensitive to capsaicin treatment in neonatal rats.6. We conclude that sodium valproate blocks plasma extravasation in the meninges through GABAA mediated postjunctional receptors probably within the meninges. The dosages required are comparable to those used clinically. Agonists and modulators at the GABAA receptor may become useful for the development of selective therapeutic agents for migraine and cluster headache.
 ...
PMID:Peripheral GABAA receptor-mediated effects of sodium valproate on dural plasma protein extravasation to substance P and trigeminal stimulation. 856 34

1. Valproic acid, useful in the treatment of migraine, is an inhibitor of gamma aminobutyric acid (GABA) aminotransferase and activator of glutamic acid decarboxylase. Its mechanism in migraine remains obscure. The effects of valproic acid (2-propylpentanoic acid) were examined on the number of cells expressing c-fos-like immunoreactivity (c-fos-LI), a marker of neuronal activation, within the trigeminal nucleus caudalis (lamina I, IIo, TNC) 2 h after intracisternal injection of the irritant, capsaicin (0.1 ml; 15.25 micrograms ml-1), in urethane-anaesthetized Hartley guinea-pigs. Positive cells were counted in eighteen sections (50 microns) at three representative levels (rostral, middle and caudal) within lamina I, IIo of the TNC in 90 animals. 2. Numerous cells were labelled after capsaicin instillation (244 +/- 25; 1 ml; 15.25 mM) but not after capsaicin vehicle (11 +/- 1). Positive cells were also found within the medial reticular nucleus, the area postrema and the nucleus of the solitary tract. A similar distribution has been demonstrated previously after application of intracisternal irritants such as autologous blood or carrageenin. 3. Valproate (> or = 10 mg kg-1, i.p.) reduced labelled cells by 52% (P < 0.05) in lamina I, IIo but not within the area postrema, the nucleus of the solitary tract or the medial reticular nucleus. A similar finding was obtained previously after administration of sumatriptan, dihydroergotamine or the NK1 receptor antagonist RPR 100,893. 4. Pretreatment with bicuculline (30 micrograms kg-1; i.p.), a GABAA antagonist, but not phaclofen (1 mg kg-1) a GABAB antagonist, reversed the effect of valproate and increased c-fos positive cells within lamina I, IIo. Somewhat paradoxically, bicuculline by itself (30 micrograms kg-1 i.p.) decreased the number of labelled cells suggesting that more than a single GABAergic mechanism can suppress c-fos expression. 5. We conclude that the mechanism of action of valproate is mediated via GABAA receptors. Since valproate decreases both c-fos expression and as previously shown, neurogenic inflammation within the meninges, the GABAA receptor complex might provide an important target for drug development in migraine and related headaches.
 ...
PMID:Attenuation by valproate of c-fos immunoreactivity in trigeminal nucleus caudalis induced by intracisternal capsaicin. 871 96

Valproic acid has been shown to be effective in migraine prophylaxis. Its method of action is believed to be the inhibition of gamma-aminobutyric acid transaminase. The therapeutic dose needed to prevent migraine headaches has been examined in several studies, yet the optimum dose has not been found. In this case report, valproic acid was given to a 24-year-old woman with chronic headaches at 1000 mg per day. Her headaches resolved for 2 months. She tapered herself off of the medication, and her headaches returned. She was restarted at 500 mg per day of valproic acid and again, her headaches resolved. She preferred being on the lower dose which she found as effective as the higher dose. Her case makes two interesting points. The first is that lower dosages of valproic acid may be as effective as higher ones in headache prophylaxis. The second is that more studies looking at dose ranges are needed to correlate effectiveness with daily requirements.
Headache 1996 Sep
PMID:High-dose versus low-dose valproic acid as a prophylactic medication. 882 9

Gamma-aminobutyric acid (GABA) receptors are ubiquitous inhibitory receptors in the central and peripheral nervous systems. Valproic acid (2-propylpentanoic acid), which enhances GABA synthesis and blocks degradation, is useful in migraine treatment and may act through activation of GABA receptors to modulate trigeminal nociceptive neurons innervating the meninges. To investigate this possibility, we tested the effect of valproate and allopregnanolone, a metabolite of progesterone, which binds and modulates the GABA receptor in an animal model of cephalic pain. One hundred ten Hartley guinea pigs were pretreated with either valproate or allopregnanolone 30 minutes prior to activation of trigeminal afferent fibers via intracisternal injection of the irritant, capsaicin. The effects of valproic acid and allopregnanolone were examined on c-fos expression within the trigeminal nucleus caudalis (lamina I, II), the termination site for small unmyelinated C fibers projecting from the meninges. C-fos positive cells were counted at three representative levels (rostral, middle, and caudal) by an observer naive to the treatment group. We found that valproate (> or = 10 mg/kg, IP) reduced labeled cells by 52% (P < 0.05) and allopregnanolone (> or = 100 mg/kg, IP) reduced labeled cells by 42% (P < 0.01). Bicuculline (GABAA antagonist), but not phaclofen (GABAB antagonist), blocked the valproate effect, thereby documenting the importance of GABAA receptors. We conclude that the attenuation of c-fos-LI by valproate and allopregnanolone is mediated via GABAA receptors. These studies complement prior experiments showing that valproic acid and allopregnanolone block neurogenic inflammation within the meninges via GABAA receptor-mediated mechanisms. The findings suggest a potential strategy for discovering new antimigraine drugs with high affinity for the GABAA receptor and its modulatory sites.
Headache
PMID:Wolff Award 1996. The actions of valproate and neurosteroids in a model of trigeminal pain. 899 May 96

Valproate has been shown to be an effective prophylactic treatment in migraine. Investigation of the mechanism of its antimigraine action is difficult due to the broad range of its biochemical effects and the complex nature of migraine pathophysiology. Valproate increases brain GABA levels and, in doing so, may suppress migraine-related events in the cortex, perivascular parasympathetics or trigeminal nucleus caudalis. There is experimental evidence that it suppresses neurogenic inflammation and directly attenuates nociceptive neurotransmission. In addition, valproate reportedly alters levels of excitatory and inhibitory neurotransmitters and exerts direct effects on neuronal membranes in vitro. Valproate's observed effect may ultimately result from a combination of actions at different loci.
Cephalalgia 1997 Apr
PMID:Possible mechanisms of valproate in migraine prophylaxis. 913 44

Panic disorder, a psychiatric disorder characterised by frequent panic attacks, is the most common anxiety disorder, affecting 2 to 6% of the general population. No one line of treatment has been found to be superior, making a risk-benefit assessment of the treatments available useful for treating patients. Choice of treatment depends on a number of issues, including the adverse effect profile, efficacy and the presence of concomitant syndromes. Tricyclic antidepressants (TCAs) are beneficial in the treatment of panic disorder. They have a proven efficacy, are affordable and are conveniently administered. Adverse effects, including jitteriness syndrome, bodyweight gain, anticholinergic effects and orthostatic hypotension are commonly associated with TCAs, but can be managed successfully. Selective serotonin (5-hydroxytryptamine; 5HT) reuptake inhibitors are also potential first line agents and are well tolerated and effective, with a favourable adverse effects profile. There is little risk in overdose or of anticholinergic effects. Adverse effects include sedation, dyspepsia and headache early in treatment, and sexual dysfunction and increased anxiety, but these can be effectively managed with proper dosage escalation and management. Benzodiazepines are an effective treatment, providing short-term relief of panic-related symptoms. Patients respond to treatment quickly, providing rapid relief of symptoms. Adverse effects include ataxia and drowsiness, and cognitive and psycho-motor impairment. There are reservations over their first-line use because of concerns regarding abuse and dependence. Monoamine oxidase inhibitors, because of their adverse effects profile, potential drug interactions, dietary restrictions, gradual onset of effect and overdose risk, are not considered to be first-line agents. They are effective however, and should be considered for patients with refractory disease. Valproic acid (valproate sodium), while not intensively studied, shows potential for use in panic disorder. More studies are needed in this area before the available data can be confirmed. As a supplement to drug therapy, cognitive behavioural therapy is effective. It is well tolerated, and may be beneficial in certain clinical situations. Its main drawback is the time commitment and effort needed to be made by the patient.
 ...
PMID:A risk-benefit assessment of pharmacological treatments for panic disorder. 963 87


1 2 3 4 5 Next >>