Optimizing Rectal Administration
In situations where swallowing medication is difficult or not possible alternate routes of medication administration are needed. These situations can occur for various reasons, such as severe nausea and vomiting, an obstruction of the gastrointestinal tract, trauma that impedes swallowing, debility or lack of consciousness.
Commonly-Used Alternate Administration Routes
Although intravenous administration is the most commonly used alternate route in acute care settings, it is rarely used in the hospice setting. Intravenous (IV) medication delivery is costly, requires a relatively high level of care, training, and support, and can lead to iatrogenic complications, such as infection, venous damage, and pain. Subcutaneous medication delivery is more common in hospice than IV, but it is also expensive and can cause infection, pain, and swelling. In addition, patients may not have enough subcutaneous fat to provide an adequate site of delivery.
Sublingual medication delivery is frequently used in the hospice setting. Its non-invasive nature and easy application by caregivers make this route favorable. Unfortunately few medications absorb well sublingually and those that don’t must work their way into the digestive system in order to be effective. Small volumes must be given to avoid aspiration by the patient.
Additional routes include transdermal and inhalation. While these routes are being researched extensively in the pharmaceutical sector, very few medications can be effectively administered to attain adequate bioavailability.
The Rectal Route: Effective but Challenging with Suppositories
The rectal route of administration is effective because the rectal mucosa is highly vascularized tissue allowing rapid and effective absorption; a high percentage of absorptive cells in the tissue also capture water and salts quickly, enhancing the absorption of medications. The effectiveness of the rectal route to deliver medication has been well established clinically; however, it is often avoided due to the numerous downsides associated with traditional forms of rectal drug administration.
For medications that are not already in suppository form, rectal administration can be ineffective. Suppositories can also pose various challenges and be ineffective if the rectum is too dry. They can also be invasive, painful, and even traumatic for the patient, especially if inserted several times daily. Suppositories may also require compounded medications that can be more expensive and difficult to procure in a timely manner compared to off-the-shelf oral formulations. Finally, suppositories may be uncomfortable for patients with bone pain or other discomfort who suffer from the repositioning required for each conventional rectal drug administration, especially before medication takes effect.
A New Alternative: The Macy Catheter™
The Macy Catheter is an innovative medical device that provides a discreet, comfortable and easy alternative to deliver medication through the rectal route. Once the Macy Catheter is placed by a clinician, the medication port is easily and discreetly accessible on the patient’s leg or abdomen, allowing for repeated delivery of medication without the need to invade the patient’s privacy or reposition the patient. The inflated retention balloon is smaller and softer than typical stool in the rectum, so defecation is unlikely to be stimulated and the patient is unlikely to feel the balloon. By making rectal access comfortable and practical, and by providing a way to deliver and retain liquid formulations in the distal rectum, the Macy Catheter allows practitioners within the healthcare system to leverage the established benefits of rectal administration more broadly. Patients often need medication when the oral route is compromised, and the Macy Catheter is designed to make the rectal route a practical alternative for those medications that can be prescribed per rectum.
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