Amitriptyline
Severe
Database
Drug interaction classified as: synergy.
Source: DDInter
Drug reference
Norepinephrine
Endogenous catecholamine vasopressor (alpha>beta-1 agonist) · Vasopressor
Also known as Noradrenaline, Levophed, Norepinephrine Bitartrate
START
IV infusion (central line) 0.05–0.1 mcg/kg/min, titrate to MAP ≥65 mmHg
TYPICAL MAX
Titrated to MAP (no fixed ceiling — high dose = refractory shock, consider adjunct vasopressor)
STOP IF
Extravasation (stop, phentolamine to site), severe digital/mesenteric ischaemia, severe hypertension/arrhythmia
WATCH
Continuous arterial BP/MAP, ECG, perfusion/extremities, infusion site (prefer central line), volume status
CDSCO approvedSchedule HATC C01CA03
KDIGO 2024 + manufacturer label
- ONSET
- 36s · onset (seconds)
- PEAK
- 2min · peak (~2 min)
- t½
- 2min · plasma t½ (~2 min)
- DURATION
- 2min · offset (1–2 min)
EXCRETION
COMT/MAO metabolism; renal inactive metabolites
route + CYP
INTERACTIONS
12 major
SEVERE in our sources
PREGNANCY
Use for life-threatening maternal hypotension/shock — uteroplacental vasoconstriction risk; benefit usually outweighs
FDA category + note
Top interactionssee all 12 →
- AmitriptylineSevereDatabaseDDInter
- AmoxapineSevereDatabaseDDInter
- ClomipramineSevereDatabaseDDInter
- DesfluraneSevereDatabaseDDInter
Available in India
24 branded formulations. Look up specific brands in the Drugs workspace.
Mechanism
Potent alpha-1 (and alpha-2) adrenoceptor agonism causing arterial/venous vasoconstriction with modest beta-1 inotropy/chronotropy → increased systemic vascular resistance and mean arterial pressure; first-line vasopressor in septic shock.
Indications
Septic and other vasodilatory shock (first-line vasopressor)Acute hypotension refractory to fluidsAdjunct in cardiac arrest/post-resuscitation hypotension
Dosing
- Adult
- IV infusion via central line: start 0.05–0.1 mcg/kg/min (or 8–12 mcg/min), titrate to target MAP (commonly ≥65 mmHg); usual range up to ~1 mcg/kg/min.
- Pediatric
- 0.05–2 mcg/kg/min titrated (PICU).
- Renal adjustment
- No specific adjustment.
- Hepatic adjustment
- No specific adjustment.
- Geriatric
- Titrate cautiously; arrhythmia/ischaemia risk.
- Max dose
- Titrated to MAP target (no fixed ceiling; high-dose indicates refractory shock)
Pharmacokinetics
Onset
Rapid (seconds–1 min)
Peak effect
~1–2 min
Duration
1–2 min after stopping
Half-life
~2–2.5 min
Bioavailability
IV only
Protein binding
~25–50%
Metabolism
COMT/MAO (rapid)
Excretion
Renal (inactive metabolites — VMA/normetanephrine)
Contraindications
- Hypovolaemia not yet corrected (correct volume first where possible)
- Caution: mesenteric/peripheral vascular thrombosis, profound hypoxia/hypercarbia
- Hypersensitivity to formulation components (sulfites)
Side effects
Common
Reflex bradycardiaHypertension (excessive)Anxiety, headachePeripheral vasoconstriction/pallorInjection-site reaction
Serious
- Tissue ischaemia/necrosis (extravasation or excessive dose) — digital, mesenteric, renal
- Severe hypertension → cerebral haemorrhage
- Arrhythmia/myocardial ischaemia
- Acrocyanosis/limb gangrene
Pregnancy & lactation
Pregnancy
Use for life-threatening maternal hypotension/shock — uteroplacental vasoconstriction risk; benefit usually outweighs
Lactation
Acute critical-care use; negligible relevance (very short t½)
Drug interactions
Amoxapine
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Clomipramine
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Desflurane
Severe
Database
Clinical effect not specified
Source: DDInter
Desipramine
Severe
Database
Clinical effect not specified
Source: DDInter
Dihydroergotamine
Severe
Database
Clinical effect not specified
Source: DDInter
Doxepin
Severe
Database
Clinical effect not specified
Source: DDInter
Enflurane
Severe
Database
Clinical effect not specified
Source: DDInter
Ergometrine
Severe
Database
Clinical effect not specified
Source: DDInter
Ergotamine Tartrate
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Halothane
Severe
Database
Clinical effect not specified
Source: DDInter
Imipramine
Severe
Database
Antidepressant actions and some adverse effects.
Not explicitly stated.
Source: DDInter
Related guidelines
Ask House about Norepinephrine
Continue into a citation-backed clinical answer with the drug context already attached.
Sources: Goodman & Gilman 14e, Harrison 22e, Katzung, BNF·Verified: 2026-05-19 · House clinical team·Cockpit curated: 2026-05-19