Mechanism of Action:
Centrally-acting cholinesterase inhibitor (competitive and reversible). It elevates acetylcholine in cerebral cortex by slowing the degradation of acetylcholine. Modulates nicotinic acetylcholine receptor to increase acetylcholine from surviving presynaptic nerve terminals. May increase glutamate and serotonin levels.
Method of Administration:
4 mg twice daily for 4 weeks; if tolerated, increase to 8 mg twice daily for ≥4 weeks; if tolerated, increase to 12 mg twice daily. Range: 16 to 24 mg daily in 2 divided doses.
Notes
Hypersensitivity to galantamine or any component of the formulation.
Interactions:
Anticholinergic Agents: Acetylcholinesterase Inhibitors may diminish the therapeutic effect of Anticholinergic Agents. Anticholinergic Agents may diminish the therapeutic effect of Acetylcholinesterase Inhibitors. Risk C: Monitor therapy
Antipsychotic Agents: Acetylcholinesterase Inhibitors (Central) may enhance the neurotoxic (central) effect of Antipsychotic Agents. Severe extrapyramidal symptoms have occurred in some patients. Risk C: Monitor therapy
Beta-Blockers: Acetylcholinesterase Inhibitors may enhance the bradycardic effect of Beta-Blockers. Risk C: Monitor therapy
Bradycardia-Causing Agents: May enhance the bradycardic effect of other Bradycardia-Causing Agents. Risk C: Monitor therapy
Corticosteroids (Systemic): May enhance the adverse/toxic effect of Acetylcholinesterase Inhibitors. Increased muscular weakness may occur. Risk C: Monitor therapy
CYP2D6 Inhibitors (Strong): May increase the serum concentration of Galantamine. Risk C: Monitor therapy
CYP3A4 Inhibitors (Strong): May increase the serum concentration of Galantamine. Risk C: Monitor therapy
Dipyridamole: May diminish the therapeutic effect of Acetylcholinesterase Inhibitors. Risk C: Monitor therapy
Fexinidazole: Bradycardia-Causing Agents may enhance the arrhythmogenic effect of Fexinidazole. Risk X: Avoid combination
Fingolimod: Bradycardia-Causing Agents may enhance the bradycardic effect of Fingolimod. Management: Consult with the prescriber of any bradycardia-causing agent to see if the agent could be switched to an agent that does not cause bradycardia prior to initiating fingolimod. If combined, perform continuous ECG monitoring after the first fingolimod dose. Risk D: Consider therapy modification
Pregnancy and Lactation:
Adverse events have been observed in animal reproduction studies.
The decision to breastfeed during therapy should consider the risk of infant exposure, the benefits of breastfeeding to the infant, and the benefits of treatment to the mother.
Warning and Precaution:
- CNS depression: May cause CNS depression, which may impair physical or mental abilities; patients must be cautioned about performing tasks that require mental alertness (eg, operating machinery or driving).
- Extrapyramidal effects: May exacerbate extrapyramidal symptoms due to an increase in cholinergic tone.
- Skin reactions: Skin reactions including Stevens-Johnson syndrome, acute generalized exanthematous pustulosis and erythema multiforme have been reported. Treatment discontinuation may be necessary if skin reaction occurs; if rash is suspected to be drug related, do not resume galantamine and consider alternative therapy.
- Vagotonic effects: Cholinesterase inhibitors may have vagotonic effects which may cause bradycardia and/or heart block with or without a history of cardiac disease.
- Weight loss: Weight loss has been observed; monitor body weight.
Adverse Reactions:
>10%: Gastrointestinal: Nausea (21%), vomiting (11%)
Storage:
Store below 30ºC and protect from light and moisture.