Nootropic / GABA derivative Pregnancy: Should not be used during pregnancy unless clearly necessary, when the benefit exceeds the risks — no adequate data in pregnant women; piracetam crosses the placenta and newborn levels are approximately 70% to 90% of maternal levels. Excreted in human breast milk — piracetam should not be used during breast-feeding, or breast-feeding should be discontinued (section 4.6).

Piracetam

Brand names: Nootropil

Piracetam is a pyrrolidone derivative used in the UK chiefly as an adjunctive treatment for cortical myoclonus.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Begin at 7.2 g daily, increasing by 4.8 g every three to four days

Route: Oral (tablets swallowed with liquid; may be taken with or without food)

Frequency: Daily dose divided into two or three sub-doses

Max: 24 g daily

The fetched section 4.2 extract describes the anti-myoclonic regimen only (it refers to maintaining other anti-myoclonic medicinal products and to Lance and Adams syndrome); no posology for any other indication is present in the source. Treatment with other anti-myoclonic medicinal products should be maintained at the same dosage initially and reduced if possible depending on clinical benefit. Once started, treatment should continue for as long as the original cerebral disease persists; in patients with an acute episode an attempt to decrease or discontinue should be made every 6 months by reducing piracetam by 1.2 g every two days (every three or four days in Lance and Adams syndrome, to prevent sudden relapse or withdrawal seizures). Elderly: dose adjustment is recommended where renal function is compromised, and creatinine clearance should be evaluated regularly during long-term treatment. Hepatic impairment alone: no dose adjustment needed; with concurrent renal impairment, adjust as for renal impairment. No paediatric posology is stated in the fetched section 4.2 extract — verify against a children's formulary.

Dose adjustments

Renal

Individualise the daily dose by creatinine clearance (CLcr): greater than 80 mL/min — usual daily dose in 2 to 3 divided doses; 50-79 mL/min — two-thirds of the usual daily dose in 2 or 3 divided doses; 30-49 mL/min — one-third of the usual daily dose in 2 divided doses; less than 30 mL/min — one-sixth of the usual daily dose as a single intake; end-stage renal disease — contraindicated. Piracetam is contraindicated where creatinine clearance is below 20 mL/min (section 4.3).

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to piracetam, to any of the excipients, or to other pyrrolidone derivatives
Severe renal impairment (creatinine clearance less than 20 mL/min)
Cerebral haemorrhage
Huntington's chorea

Side effects

Nervousness (common); depression (uncommon); agitation, anxiety, confusion, hallucination (not known)
Hyperkinesia (common); somnolence (uncommon); ataxia, balance impaired, aggravated epilepsy, headache, insomnia (not known)
Weight increased (common)
Asthenia (uncommon)
Haemorrhagic disorder (not known); anaphylactoid reaction and hypersensitivity (not known)
Abdominal pain, diarrhoea, nausea, vomiting; angioneurotic oedema, dermatitis, pruritus, urticaria (not known)

Interactions

Effect on platelet aggregation — caution in severe haemorrhage, patients at risk of bleeding (e.g. gastrointestinal ulcer), disorders of haemostasis, previous haemorrhagic stroke, major surgery including dental surgery, and patients taking anticoagulants or antiplatelet drugs including low-dose acetylsalicylic acid (section 4.4)
Thyroid extract (T3 + T4) — confusion, irritability and sleep disorder reported during concomitant treatment
Acenocoumarol — piracetam 9.6 g/day did not change the acenocoumarol dose needed for INR 2.5 to 3.5, but significantly decreased platelet aggregation, beta-thromboglobulin release, fibrinogen and von Willebrand factor levels and blood/plasma viscosity compared with acenocoumarol alone
Metabolic (cytochrome P450) interactions are considered unlikely — approximately 90% of a dose is excreted unchanged in urine
Antiepileptic drugs — piracetam 20 g daily for 4 weeks did not modify peak levels (source text truncated; verify against the current SPC)

Clinical monograph

How it works

Its mechanism is not fully established; it is thought to modulate neuronal membrane fluidity and neurotransmission and to influence cortical excitability, but the precise mode of action is uncertain.

Prescribing in practice

It is mainly renally excreted, so the dose must be reduced in renal impairment and it should be avoided in severe renal failure.
Avoid abrupt withdrawal in myoclonus, as this may precipitate seizures or a rebound in myoclonic jerks.
It is usually added to existing antimyoclonic therapy rather than used alone, and is taken in divided doses through the day.

Monitoring

Monitor renal function and seizure or myoclonus control, and review for adverse effects such as weight gain, nervousness or hyperkinesia.

Counselling the patient

Do not stop this medicine suddenly, as your myoclonus could worsen.
Report any unusual restlessness, agitation, or significant weight change to your team.

Evidence & guidelines

Its use in cortical myoclonus is supported by clinical trial and long-standing practice as an add-on agent, as reflected in current prescribing references.

Reference: SmPC; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Pathways