Summary
Standard anesthetic practice uses continuous infusions of 0.05-0.25 ug/kg/min; analgesia ceases within approximately 5 minutes of pump stoppage due to ester hydrolysis. Context-sensitive half-life is 2-4 minutes regardless of infusion length. Bolus dosing outside monitored settings is strongly discouraged because apnea can occur before the syringe is empty. Remifentanil is a metabolic soft drug rapidly hydrolyzed by nonspecific tissue and plasma esterases.
Dose Information
| ROA | Light | Common | Strong | Heavy |
|---|---|---|---|---|
| Intravenous | 10-20ug | - | - | 100+ug(dangerous)+ |
Light
Common
Strong
Heavy
Onset, Duration & After-effects
| ROA | Onset | Peak | Offset | After Effects |
|---|---|---|---|---|
| Intravenous | 1-1 min | 1-2 min | 3-5 min | 5-15 min |
Tolerance
Build-up
develops within days of regular use; analgesic tolerance faster than respiratory depression tolerance
Reset
7–14 days for partial reset; full reset may take weeks — tolerance loss greatly increases overdose risk
Effects
Positive
- Physical euphoria
- Pain relief
- Analgesia
Negative
- Respiratory depression
- Bodily control impairment
- Nausea
- Sedation
- Itchiness
- Pupil constriction
- Muscle rigidity
Positive
- Cognitive euphoria
- Reduced anxiety
- Euphoria
- Anxiety suppression
- Mood lift
Negative
- Constipation
- Compulsive redosing
- Dizziness
- Motor control loss
- Physical autonomy
Positive
- Warmth
- Color enhancement
- Increased music appreciation
- Brightened colour
Negative
- Light sensitivity
- Appetite suppression
- Disinhibition
- Dehydration
- Dulled perception
- Drifting