Piracetam

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Piracetam chemical structure
Piracetam
Systematic (IUPAC) name
2-oxo-1-pyrrolidineacetamide
Identifiers
CAS number 7491-74-9
ATC code N06BX03
PubChem  ?
Chemical data
Formula C6H10N2O2
Mol. weight 142.156 g/mol
Pharmacokinetic data
Bioavailability ~100 %
Metabolism  ?
Half life 4-5 hours
Excretion Urinary
Therapeutic considerations
Pregnancy cat.

?
Legal status

UK: POM; legal to import
Orphan drug
Routes Oral and parenteral

Piracetam (brand name: Nootropil®, Myocalm®), is a cerebral function regulating drug which is claimed to be able to enhance cognition as well as slow down brain aging. Piracetam's chemical name is 2-oxo-pyrrolidone, or 2-oxo-1-pyrrolidine acetamide. Piracetam is a cyclic derivative of GABA. It is one of the racetams, and is similar to the amino acid pyroglutamate. Though rare in the United States, piracetam is commonly prescribed in Europe for a variety of conditions.

Contents

[edit] Effects

Several meta-reviews of literature on piracetam indicate that piracetam increases performance on a variety of cognitive tasks among dyslexic children, though this may reflect its enhancement of cross-hemispheric communication and of cognitive function in general, rather than a specific improvement in whatever causes dyslexia. Piracetam also seems to inhibit brain damage caused by a variety of factors including hypoxia and excessive alcohol consumption.[1] [2]

Piracetam has been studied in an extensive number of clinical experiments, and has shown positive results in the treatment of post-stroke aphasia, epilepsy, cognitive decline following heart and brain surgery, dementia[3], and myoclonus,[4] [5]and some believe that understanding the mechanism it works through can teach us about the role of inter-hemispheric communication in the brain.[citation needed]

[edit] Mechanisms of action

The mechanism of action of piracetam is not known. [6] It has been found to increase blood flow and oxygen consumption in parts of the brain. [7]

Piracetam may facilitate movement of information between the brain's two hemispheres via the corpus callosum, and improves the function of the neurotransmitter acetylcholine via muscarinic cholinergic (ACh) receptors which are implicated in memory processes.[citation needed] Furthermore, Piracetam may have an effect on NMDA glutamate receptors which are involved with learning and memory processes.[citation needed] Piracetam is thought to increase cell membrane permeability. [8][9]Finally, Piracetam may exert its global effect on brain neurotransmission via modulation of ion channels (i.e., Ca2+, K+).[10] It has been found to increase oxygen consumption in the brain.

[edit] History

Piracetam was first synthesized in 1964 by scientists at the Belgian pharmaceutical company UCB led by Dr Corneliu E. Giurgea. The drug was the first of the so-called nootropics ("smart drugs" or "cognitive enhancers"), that is, substances which purportedly enhance mental performance. The term nootropic was coined by Giurgea. Nootropil was launched clinically by UCB in the early 1970s and remains an important product of that company in Europe.

[edit] Approval and usage

Piracetam is primarily used in Europe. Piracetam is legal to import into the United Kingdom for personal use with or without prescription as with other prescription-only drugs. As of June of 2006, piracetam is not regulated in the United States (it is neither a controlled substance nor a prescription drug but instead sold as a dietary supplement).

[edit] Dosage

Piracetam is usually supplied in 800 mg tablets or capsules. The recommended dosage varies based on the indication, usually ranging from 1.6-9.6 grams daily (2-12 pills daily). Some people report faster results when taking 1-2 pills every hour for 4-6 hours or taking 4-8 pills at once for the first few days to notice an effect.

It has been studied up to 45 grams daily without major side effects.[citation needed]

It has no known LD-50 in humans when taken orally.[11]

In the US, and possibly other countries in which Piracetam is unregulated, it is often sold in bulk as a powder. It is up to the user to decide how they want to ingest said powder; orange juice is frequently cited as a good mixer to mask the taste.

[edit] Contraindications

Piracetam is contra-indicated in patients with severe renal impairment (renal creatinine clearance of less than 20 ml per minute), hepatic impairment and to those under 16 years of age. It is also contraindicated in patients with cerebral haemorrhage and in those with hypersensitivity to piracetam, other pyrrolidone derivatives or any of the excipients .

[edit] Special warnings and precautions for use

Due to the effect of piracetam on platelet aggregation, caution is recommended in patients with underlying disorders of haemostasis, major surgery or severe haemorrhage.

Abrupt discontinuation of treatment should be avoided as this may induce myoclonic or generalised seizures in some myoclonic patients.

As piracetam is almost exclusively excreted by the kidneys caution should be exercised in treating patients with known renal impairment. In renally impaired and elderly patients, an increase in terminal half-life is directly related to renal function as measured by creatinine clearance. Dosage adjustment is therefore required in those with mild to moderate renal impairment and elderly patients with diminished renal function.

[edit] Undesirable effects

Piracetam has been found to have very few side effects, and those it has are typically "few, mild, and transient." [12]

A large-scale, 12-week trial of high-dose piracetam found no adverse effects occured in the group taking piracetam as compared to the [placebo] group. [13]

Many other studies have likewise found piracetam to be well-tolerated. [14] [15]

Piracetam use has caused the development of multiple chemical sensitivities in some users.

[edit] References

  1. ^ "Can nootropic drugs be effective against the impact of ethanol teratogenicity on cognitive performance?" Eur Neuropsychopharmacol. 2001 Feb;11(1):33-40.
  2. ^ "Piracetam and vinpocetine exert cytoprotective activity and prevent apoptosis of astrocytes in vitro in hypoxia and reoxygenation." Neurotoxicology. 2002 May;23(1):19-31.
  3. ^ "Clinical efficacy of piracetam in cognitive impairment: a meta-analysis."Dement Geriatr Cogn Disord. 2002;13(4):217-24.
  4. ^ "Long-term efficacy and safety of piracetam in the treatment of progressive myoclonus epilepsy."Arch Neurol. 2001 May;58(5):781-6.
  5. ^ Effectiveness of piracetam in cortical myoclonus." Mov Disord. 1993;8(1):63-8.
  6. ^ "Piracetam and other structurally related nootropics." Brain Res Brain Res Rev. 1994 May;19(2):180-222.
  7. ^ "Cerebral blood flow effects of piracetam, pentifylline, and nicotinic acid in the baboon model compared with the known effect of acetazolamide." Arzneimittelforschung. 1996 Sep;46(9):844-7.
  8. ^ "Piracetam--an old drug with novel properties?" Acta Pol Pharm. 2005 Sep-Oct;62(5):405-9.
  9. ^ "Piracetam: novelty in a unique mode of action." Pharmacopsychiatry. 1999 Mar;32 Suppl 1:2-9.
  10. ^ "Piracetam and other structurally related nootropics." Brain Res Brain Res Rev. 1994 May;19(2):180-222.
  11. ^ "Piracetam and other structurally related nootropics." Brain Res Brain Res Rev. 1994 May;19(2):180-222.
  12. ^ "Piracetam relieves symptoms in progressive myoclonus epilepsy: a multicentre, randomised, double blind, crossover study comparing the efficacy and safety of three dosages of oral piracetam with placebo." Neurol Neurosurg Psychiatry. 1998 Mar;64(3):344-8.
  13. ^ "The clinical safety of high-dose piracetam--its use in the treatment of acute stroke." Pharmacopsychiatry. 1999 Mar;32 Suppl 1:33-7.
  14. ^ "Long-term efficacy and safety of piracetam in the treatment of progressive myoclonus epilepsy." Arch Neurol. 2001 May;58(5):781-6.
  15. ^ "Piracetam relieves symptoms in progressive myoclonus epilepsy: a multicentre, randomised, double blind, crossover study comparing the efficacy and safety of three dosages of oral piracetam with placebo." J Neurol Neurosurg Psychiatry. 1998 Mar;64(3):344-8.

[edit] See also

[edit] External links


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Adrafinil, Armodafinil, Caffeine, Modafinil, Nicotine

Sympathomimetic amines (R01, A08, and others) edit

Aminorex, Amphetamine, Benzylpiperazine, Cathinone, CFT, Chlorphentermine, Clobenzorex, Cocaine, Cyclopentamine, Diethylpropion, Ephedrine, Fenfluramine, Mazindol, 4-Methyl-aminorex, Methylone, Methylphenidate, Pemoline, Phendimetrazine, Phenmetrazine, Phentermine, Phenylephrine, Propylhexedrine, Pseudoephedrine, Sibutramine, Synephrine
See also amphetamines
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