Infusion pumps disadvantages

When the oral route is unavailable opioids may be administered by continuous infusion (pump) and when appropriate under control by the patient - advantage constant therapeutic plasma level disadvantage indwelling catheter. When constipation becomes intolerable morphin can be applied near the spinal cord permitting strong analgesic effect at much lower total dosage. 

However, one disadvantage associated with the use of most recombinant molecules is their rapid clearance. Because of this rapid clearance, recombinant molecules require repeated administration to achieve biological efficacy. Initially, continuous infusion was used to address this pharmacological deficiency. Continuous infusion has the advantage of delivering drugs in a controlled manner and is particularly appropriate when it is important to maintain constant plasma drug concentrations. However, the requirement for continuous venous access and the use of ambulatory pumps limits its use. 

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