Dosing and uses of Razadyne (galantamine)
Adult dosage forms and strengths
tablets
- 4mg
- 8mg
- 12mg
tablets, extended-release
- 8mg
- 16mg
- 24mg
oral solution
- 4mg/mL
Alzheimer Disease
InitiaL
- Conventional: 4 mg PO q12hr
- ER: 8 mg PO qAM
Maintenance
- Conventional: Titrate to 8-12 mg PO q12hr; increase by 4 mg q12hr at no less than 4 week intervals
- ER: 16-24 mg PO qAM; increase by 8 mg/d at no less than 4 week intervals
Hepatic Impairment
Moderate: (Child-Pugh score 7-9): Not to exceed 16 mg/day
Severe: Not recommended
Renal Impairment
Moderate: Not to exceed 16 mg/day
Severe (CrCl <9 mL/min): Not recommended
Administration
Take with food
Conversion from galantamine tablets and oral solution to galantamine ER should occur at same daily dosage with the last dose of galantamine tablets/oral solution taken in evening and starting galantamine ER once daily treatment next morning
Pediatric dosage forms and strengths
Not recommended
Razadyne (galantamine) adverse (side) effects
>10%
Nausea (20-25%)
Diarrhea (11-15%)
Vomiting (11-15%)
1-10%
Abdominal pain
Anorexia
Muscle cramp
Fatigue
Dizziness
Headache
Weight loss
Depression
Insomnia
UTI
Somnolence
Anemia
Syncope
Bradycardia
Other Information
Rare: bradycardia, AV block
Warnings
Contraindications
Hypersensitivity
Cautions
Moderate hepatic or renal impairment: max 8 mg q12hr (conventional) or 16 mg qDay (ER)
Not recommended in severe hepatic or renal impairment
Renamed Razadyne from Reminyl in the US to avoid confusion with AmaryL
Serious skin reactions may occur; discontinue at first appearance of skin rash
All patients should be considered at risk for adverse effects on cardiac conduction, including bradycardia and AV block, due to vagotonic effects on sinoatrial and atrioventricular nodes
Active or occult gastrointestinal bleeding: monitor, especially those with an increased risk for developing ulcers
Cholinomimetics may cause bladder outflow obstruction
Monitor for respiratory adverse events in patients with a history of severe asthma or obstructive pulmonary disease
Pregnancy and lactation
Pregnancy category: B
Lactation: unknown
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Razadyne (galantamine)
Mechanism of action
Derived from daffodil bulbs
Increases acetylcholine from surviving presynaptic nerve terminals by modulating the nicotinic acetylcholine receptor. Glutamate and serotonin levels may increase
Pharmacokinetics
Half-Life: 7 hr
Peak Plasma Time: 1 hr
Bioavailability: 90%
Protein Bound: 18%
Vd: 175 L
Metabolism: CYP2D6 & CYP3A4
Excretion: Urine
