Galantamine
From SEHK Wiki
Introduction
Galantamine Hydrobromide, is a reversible inhibitor of acetylcholinesterase. It also has an intrinsic action on nicotinic receptors. It is used for the treatment of mild to moderate dementia in Alzheimer’s disease.
| Generic Name 藥名 | HA Code 藥物代碼 | Classification藥物分類 |
|---|---|---|
| Galantamine HBR Prolonged Release Cap 8mg | GALA04 | P1S1S3 |
| Galantamine HBR Prolonged Release Cap 16mg | GALA05 | P1S1S3 |
| Galantamine HBR Prolonged Release Cap 24mg | GALA06 | P1S1S3 |
Mechanism of Action
Acetylcholinesterase inhibiting drug
Dosage
By Oral: initially 4 mg twice daily for 4 weeks increased to 8 mg twice daily for 4 weeks; maintenance 8-12 mg twice daily according to response and tolerance.
A modified-release preparation is also available for once-daily use. Clinical benefit should be assessed on a regular basis.
Reductions in dose may be necessary in patients with hepatic or renal impairment.
Side Effects=
Common side effects include
- Nausea and vomiting
- difficulty sleeping
- aggression
- Loss of appetite
- Diarrhoea
- Feeling tired
- Muscle cramps
These effects usually last 1 – 3 weeks and then lessen
Serious side effects may include:
- Abnormal heart rhythms
- Difficulty emptying urine from the bladder
- seizures
Pharmacokinetics
| Oral bioavailability | Donepezil hydrochloride is rapidly and well absorbed from the gastrointestinal tract with an oral bioavailability of about 90%. Plasma protein binding is about 18%. |
|---|---|
| Onset of action | Peak plasma levels in about one hour after ingestion from immediate-release preparations; 4 to 5 hours after a dose of modified-release formulations |
| Metabolism | Partially metabolized by CYP2D6, CYP3A4 |
| Elimination half-life | 7 to 8 hours |
