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)

Donepezil (donepezil hydrochloride, E-2020, Aricept, Eisai), launched in March 1997, was the first drug to be marketed for the symptomatic treatment of Alzheimer's disease (AD) in the UK. It had been launched a year earlier in the US where clinicians had already had experience of tacrine (THA). Donepezil is a piperidine based, potent, specific, non-competitive and reversible inhibitor of acetylcholinesterase (AChE). It is structurally dissimilar from other established cholinesterase inhibitors, namely THA (an acridine compound) and the carbamates, physostigmine and rivastigmine and has a pharmacokinetic and tolerability profile distinct from these agents. Experimentally, donepezil inhibits AChE activity in human erythrocytes and increases extracellular acetylcholine levels in the cerebral cortex and the hippocampus of the rat. Pharmacologically, donepezil has a half-life of approximately 70 h lending itself to once daily administration. The most common adverse events reported in clinical trials have been gastrointestinal, typically nausea, vomiting, diarrhoea and constipation. Headache, dizziness and sleep disturbance have also been reported; there has been no evidence of hepatotoxicity. Clinically a number of placebo-controlled trials have shown that donepezil 5 or 10 mg daily was associated with significant improvements in cognitive function, as assessed by the Alzheimer's disease Assessment Scale-cognitive subscale (ADAS cog) after 12 or 24 weeks treatment. Significant improvements in global function and activities of daily living have also been demonstrated after 24 weeks treatment compared with placebo in patients with mild to moderate AD. Donepezil was the first rational treatment available in the UK for this disabling condition and as such received considerable attention. Much of the original attention was negative, ostensibly based on the scientific view that there was not enough published evidence to justify widespread use, but this was driven by concerns about the potentially high drug costs if all patients with AD were eligible to receive it. Considerable data have now been produced from Phase II, III and post-marketing surveillance. This drug evaluation will review the basic pharmacology of donepezil and place it in context with the trial data and the author's clinical experience with the drug.
 ...
PMID:The pharmacology of donepezil: a new treatment of Alzheimer's disease. 1124 55

The tolerability and safety of donepezil HCI in patients with mild to moderate Alzheimer's disease (AD) were examined in an integrated analysis of phase II/III placebo-controlled trials. Patients with mild to moderately severe AD (n=1,920) were randomised to receive donepezil (n=1,291) or placebo (n=629). Adverse events, physical examinations and clinical laboratory tests were assessed. A high completion rate (79%) was achieved in these trials. Of the 1,291 patients receiving donepezil only, 142 (11%) withdrew because of an adverse event compared with 43 of the 629 (7%) placebo patients. The most common adverse events included nausea, diarrhoea, headache, insomnia, dizziness, rhinitis, vomiting, asthenia/fatigue and anorexia. Donepezil had no clinically significant effect on any laboratory evaluations and was not associated with hepatotoxicity. These results demonstrate that donepezil is well tolerated and has a favourable safety profile at clinically effective, once-daily doses of 5 mg and 10 mg.
 ...
PMID:Donepezil: tolerability and safety in Alzheimer's disease. 1246 88

The antinociceptive activity of donepezil, a novel cholinesterase inhibitor, was investigated in the mouse hot plate test. Donepezil (5 to 10 mg kg(-1) i.p.) induced a dose-dependent antinociception that reached its maximum effect 15 minutes after injection. Donepezil antinociception was prevented by the antimuscarinic drug scopolamine. At analgesic doses, donepezil did not alter gross animal behavior. These results indicate that donepezil is endowed by muscarinic antinociceptive properties, suggesting this compound as a potential therapeutic approach for the treatment of painful pathologies. Therefore, we investigated donepezil's effect in migraine. Donepezil (5 mg per os, evening assumption) was effective as a prophylatic agent in patients suffering from migraine with or without aura by reducing the number of hours with pain, the number of attacks, and the severity of the pain attack. The efficacy of donepezil was compared with that of the beta-blocker propranolol (40 mg bid per os), showing higher activity. Response rates of a large-sized open study devoid of entry criteria regarding migraine subtypes suggest the drug as an excellent prophylactic compound for migraine in general practice. Clinical results also indicate that the activation of the cholinergic system can represent a novel prophylactic approach to migraine.
Headache
PMID:Central cholinergic challenging of migraine by testing second-generation anticholinesterase drugs. 1248 11