Apalutamide
Severe
Database
Drug interaction classified as: metabolism
Source: DDInter
Drug reference
Felodipine
Dihydropyridine calcium channel blocker · Antihypertensive
START
ER 5 mg PO once daily (2.5 mg if elderly/hepatic)
TYPICAL MAX
10 mg/day
STOP IF
Severe hypotension, worsening angina, or marked oedema
WATCH
BP, peripheral oedema, heart rate; grapefruit avoidance
CDSCO approvedATC C08CA02
KDIGO 2024 + manufacturer label
- ONSET
- 3h · BP effect
- PEAK
- 4h · Tmax (ER)
- t½
- 14h · t½
- DURATION
- 1d · once-daily
EXCRETION
~70% renal as metabolites; ~10% faecal
route + CYP
INTERACTIONS
12 major
SEVERE in our sources
PREGNANCY
Avoid unless essential; limited data (animal embryotoxicity).
FDA category + note
Top interactionssee all 12 →
- ApalutamideSevereDatabaseDDInter
- BetrixabanSevereDatabaseDDInter
- CeritinibSevereDatabaseDDInter
- DolasetronSevereDatabaseDDInter
Available in India
5 branded formulations. Look up specific brands in the Drugs workspace.
Mechanism
Blocks L-type voltage-gated calcium channels in vascular smooth muscle (vascular-selective), causing peripheral arteriolar vasodilation and reduced systemic vascular resistance with minimal negative inotropy.
Indications
HypertensionChronic stable angina (adjunct)
Dosing
- Adult
- Extended-release 5 mg PO once daily; range 2.5–10 mg/day. Start 2.5 mg in elderly/hepatic impairment.
- Pediatric
- Not established.
- Renal adjustment
- No dose adjustment required.
- Hepatic adjustment
- Reduce dose / start 2.5 mg (reduced clearance); monitor BP.
- Geriatric
- Start 2.5 mg once daily.
- Max dose
- 10 mg/day
Pharmacokinetics
Onset
2–5 h (ER); BP effect within hours
Peak effect
2.5–5 h (Tmax, ER)
Duration
~24 h
Half-life
~11–16 h (ER)
Bioavailability
~15% (high first-pass; CYP3A4)
Protein binding
>99%
Metabolism
Hepatic CYP3A4 (extensive first-pass)
Excretion
~70% renal as metabolites; ~10% faecal
Contraindications
- Hypersensitivity to dihydropyridines
- Unstable angina / acute MI
- Significant aortic stenosis
- Decompensated heart failure
- Severe hepatic impairment (caution/avoid)
Side effects
Common
Peripheral oedemaHeadacheFlushingPalpitationsDizziness
Serious
- Severe hypotension
- Reflex tachycardia / angina aggravation
- Gingival hyperplasia (chronic)
Pregnancy & lactation
Pregnancy
Avoid unless essential; limited data (animal embryotoxicity).
Lactation
Limited data; caution.
Drug interactions
Betrixaban
Severe
Database
Drug interaction classified as: others
Source: DDInter
Ceritinib
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Dolasetron
Severe
Database
Clinical effect not specified
Source: DDInter
Edoxaban
Severe
Database
Clinical effect not specified
Source: DDInter
Enzalutamide
Severe
Database
Clinical effect not specified
Source: DDInter
Grapefruit Juice
Severe
Database
Gut CYP3A4 inhibition
Avoid grapefruit entirely
Source: Kimi deep-research + Cla
Itraconazole
Severe
Database
Excessive hypotension, edema
Monitor BP. Reduce felodipine dose.
Source: DDInter
Ketoconazole
Severe
Database
Drug interaction classified as: metabolism
Source: DDInter
Lumacaftor
Severe
Database
Drug interaction classified as: metabolism
Source: DDInter
Mitotane
Severe
Database
Drug interaction classified as: metabolism
Source: DDInter
Phenytoin
Severe
Database
Drug interaction classified as: metabolism
Source: DDInter
Related guidelines
Other Dihydropyridine calcium channel blocker drugs
Ask House about Felodipine
Continue into a citation-backed clinical answer with the drug context already attached.
Sources: KD Tripathi 7e, Goodman & Gilman 14e, Harrison 22e, Katzung·Verified: 2026-05-20 · House clinical team·Cockpit curated: 2026-05-20