Clarithromycin
Contraindicated
Textbook-cited
QT prolongation and ventricular arrhythmia
Concurrent use is contraindicated
Source: KDT 7e · p948
Drug reference
cisapride
Gastrointestinal prokinetic (5-HT4 agonist; WITHDRAWN/restricted) · Antiemetic
START
Use discouraged (withdrawn); restricted-access only
TYPICAL MAX
80 mg/day (historical)
STOP IF
Any QT prolongation / arrhythmia
WATCH
ECG/QT, electrolytes (K/Mg), CYP3A4 interaction list
CDSCO approvedATC A03FA02
KDIGO 2024 + manufacturer label
- ONSET
- 1h · absorption
- PEAK
- 1.5h · Tmax
- t½
- 8h · t½
- DURATION
- 7h · per dose
EXCRETION
Renal/faecal — metabolites
route + CYP
INTERACTIONS
12 major
incl. contraindicated
PREGNANCY
Avoid; limited data.
FDA category + note
Top interactionssee all 12 →
- ClarithromycinContraindicatedTextbook-citedKDT 7e · p948
- ErythromycinContraindicatedTextbook-citedKDT 7e · p948
- FluconazoleContraindicatedTextbook-citedKDT 7e · p948
- KetoconazoleContraindicatedTextbook-citedKDT 7e · p948
Mechanism
Selective 5-HT4 receptor agonist that enhances acetylcholine release from myenteric plexus, increasing GI motility (oesophageal, gastric, small-bowel and colonic); minimal antidopaminergic activity.
Indications
Historical: gastroparesis, GERD, chronic intestinal pseudo-obstruction. WITHDRAWN or restricted-access in most countries due to QT-prolongation / torsades / sudden cardiac deaths.
Dosing
- Adult
- Historical: 10–20 mg PO 4 times daily before meals/bedtime. Use generally discouraged; restricted-access programmes only.
- Pediatric
- Not recommended (case reports of fatal arrhythmia).
- Renal adjustment
- Reduce in significant impairment.
- Hepatic adjustment
- Reduce / avoid in significant impairment.
- Geriatric
- Avoid (QT/electrolyte risk).
- Max dose
- 80 mg/day (historical ceiling)
Pharmacokinetics
Onset
30–60 min (oral)
Peak effect
~1–2 h
Duration
~6–8 h
Half-life
~7–10 h
Bioavailability
Variable (~30–40%, food-dependent)
Protein binding
~97%
Metabolism
Hepatic CYP3A4 (major)
Excretion
Renal/faecal (metabolites)
Contraindications
- Existing or potential QT prolongation (electrolyte disturbance, congenital long-QT, bradycardia)
- Co-administration with CYP3A4 inhibitors / other QT-prolonging drugs
- Significant cardiac disease
- Severe hepatic / renal impairment
- Hypersensitivity
- Use generally not recommended (withdrawn/restricted)
Side effects
Common
Diarrhoea / abdominal crampsHeadacheNauseaRhinitis
Serious
- QT prolongation / torsades de pointes / sudden cardiac death (withdrawal basis)
- Severe hypersensitivity
- Seizures (rare)
Pregnancy & lactation
Pregnancy
Avoid; limited data.
Lactation
Avoid (limited data; QT concern in infants).
Drug interactions
Erythromycin
Contraindicated
Textbook-cited
QT prolongation and ventricular arrhythmia.
Concurrent use is contraindicated
Source: KDT 7e · p948
Fluconazole
Contraindicated
Textbook-cited
QT prolongation and ventricular arrhythmia.
Concurrent use is contraindicated
Source: KDT 7e · p948
Ketoconazole
Contraindicated
Textbook-cited
QT prolongation and ventricular arrhythmia
Concurrent use is contraindicated
Source: KDT 7e · p948
Azole Antifungals
Contraindicated
Textbook
Prolongs Q-Tc interval and predisposes to torsades de pointes/ventricular fibrillation, leading to serious ventricular arrhythmias and death.
Avoid combination. Cisapride was banned in India and is available only for limited investigational use in USA due to this risk.
Source: KDT 7e · p667
Amisulpride
Contraindicated
Database
Increased risk of Torsades de Pointes (TdP) and other ventricular arrhythmias
Concomitant use is contraindicated. Avoid combination.
Source: DDInter
Azithromycin
Contraindicated
Database
No significant change in plasma levels of cisapride is expected.
Caution may be exercised despite unlikelihood of interaction.
Source: DDInter
Antiarrhythmics
Contraindicated
Database
Additive QT
Contraindicated
Source: Kimi deep-research + Cla
Gatifloxacin
Contraindicated
Database
Significantly increased risk of QT interval prolongation and Torsades de Pointes, leading to potentially fatal arrhythmias.
Concomitant use is contraindicated. Avoid this combination.
Source: DDInter
Itraconazole
Contraindicated
Database
Itraconazole is a potent CYP3A4 inhibitor. Cisapride is metabolized by CYP3A4; inhibition leads to markedly elevated cisapride plasma concentrations, causing QT prolongation and torsades de pointes, which can be fatal.
CONTRAINDICATED. Do not coadminister under any circumstances. If prokinetic therapy is needed, consider metoclopramide or domperidone (with caution) as alternatives.
Source: Kimi deep-research + Cla · p948
Moxifloxacin
Contraindicated
Database
Severe QT prolongation and increased risk of Torsades de Pointes
Concomitant use is contraindicated due to high risk of life-threatening arrhythmias.
Source: DDInter
Ofloxacin
Contraindicated
Database
Increased risk of Torsades de Pointes and other ventricular arrhythmias
Concomitant use is contraindicated due to severe risk of cardiac arrhythmias. Cisapride is largely withdrawn from market but still relevant for historical context or specific regions.
Source: DDInter
Related guidelines
Ask House about cisapride
Continue into a citation-backed clinical answer with the drug context already attached.
Sources: KD Tripathi 7e, Goodman & Gilman 14e·Verified: 2026-05-20 · House clinical team·Cockpit curated: 2026-05-20