Bupropion
Severe
Database
Drug interaction classified as: metabolism.
Source: DDInter
Drug reference
Donepezil
Centrally-acting reversible acetylcholinesterase inhibitor · Cognitive Enhancer
Also known as Donepezil Hydrochloride, Aricept
START
Baseline HR and ECG (bradycardia risk). Assess GI history (PUD risk). Administer at bedtime to minimize GI side effects and insomnia. Inform patient/caregiver that benefit is modest and disease progression continues.
TYPICAL MAX
23mg only for severe Alzheimer's after 3 months at 10mg. Higher GI side effects at 23mg. Do not exceed 10mg in mild-moderate disease.
STOP IF
Syncope, HR <50 bpm, new AV block, severe GI bleeding, severe bradycardia, anaphylaxis.
WATCH
Bradycardia and syncope risk—especially with concurrent beta-blockers or calcium channel blockers. GI side effects common—take with food if needed. Cholinergic excess symptoms (salivation, lacrimation, diarrhea). Monitor weight (anorexia common).
CDSCO approvedSchedule HATC N06DA02
KDIGO 2024 + manufacturer label
- ONSET
- 1h · Onset ~1 hour
- PEAK
- 3.5h · Tmax ~3-4 hours
- t½
- 2.9d · t½ ~70 hours
- DURATION
- 1d · 24 hours (QD)
EXCRETION
Fecal as metabolites (~57%)
route + CYP
INTERACTIONS
6 major
SEVERE in our sources
PREGNANCY
Not indicated in pregnancy; animal data show no teratogenicity. Use only if clearly needed.
FDA category + note
Top interactionssee all 6 →
- BupropionSevereDatabaseDDInter
- IohexolSevereDatabaseDDInter
- IopamidolSevereDatabaseDDInter
- OzanimodSevereDatabaseDDInter
Available in India
86 branded formulations and 39 fixed-dose combinations. Look up specific brands in the Drugs workspace.
Mechanism
Selectively and reversibly inhibits acetylcholinesterase in the CNS, increasing acetylcholine concentration at cholinergic synapses, improving cholinergic neurotransmission and cognitive function in Alzheimer's disease
Indications
Alzheimer's disease (mild, moderate, and severe)Lewy body dementia (off-label)Vascular dementia (off-label, limited evidence)
Dosing
- Adult
- 5mg PO daily at bedtime x 4-6 weeks, then increase to 10mg daily. Severe Alzheimer's: may increase to 23mg daily after 3 months at 10mg.
- Pediatric
- Not indicated in children.
- Renal adjustment
- No adjustment needed (minimal renal excretion).
- Hepatic adjustment
- Mild-moderate: no adjustment. Severe: use caution (limited data).
- Geriatric
- No specific adjustment; start 5mg daily; monitor for bradycardia and syncope.
- Max dose
- 23mg/day (severe Alzheimer's only); 10mg/day (mild-moderate)
Pharmacokinetics
Onset
Cognitive improvement: 4-6 weeks; maximal benefit: 3-6 months
Peak effect
Tmax 3-4 hours; steady-state in ~15 days
Duration
24 hours (QD dosing)
Half-life
~70 hours (mean 70; range 50-100h); long half-life allows QD dosing
Bioavailability
~100%
Protein binding
~96% (albumin)
Metabolism
Hepatic via CYP2D6 (major), CYP3A4; metabolites include 6-O-desmethyldonepezil (active)
Excretion
~57% fecal (17% unchanged); ~28% renal (no unchanged drug)
Contraindications
- Hypersensitivity to donepezil or piperidine derivatives
- Severe hepatic impairment
Side effects
Common
Nausea and vomitingDiarrheaInsomnia (if taken late)Muscle crampsFatigueAnorexia / weight lossBradycardia
Serious
- Bradycardia / heart block / syncope (vagotonic effect)
- Seizures (lowers seizure threshold)
- Peptic ulcer disease / GI bleeding
- Worsening of asthma or COPD (bronchospasm)
- Urinary obstruction (BPH)
- Rhabdomyolysis (rare)
Pregnancy & lactation
Pregnancy
Not indicated in pregnancy; animal data show no teratogenicity. Use only if clearly needed.
Lactation
Excretion in breast milk unknown; not expected to be significant due to high protein binding. Use with caution.
Drug interactions
Iohexol
Severe
Database
Clinical effect not specified
Source: DDInter
Iopamidol
Severe
Database
Clinical effect not specified
Source: DDInter
Ozanimod
Severe
Database
Clinical effect not specified
Source: DDInter
Siponimod
Severe
Database
Clinical effect not specified
Source: DDInter
Tramadol
Severe
Database
.
Source: DDInter
6 additional unreviewed or low-confidence interactions hidden because their provenance or source detail is insufficient.
Related guidelines
Ask House about Donepezil
Continue into a citation-backed clinical answer with the drug context already attached.
Textbook-sourced·Sources: KD Tripathi 7e, Goodman & Gilman 14e, Katzung, BNF·Updated: 2026-05-19·Cockpit curated: 2026-05-19