Nasal drug delivery administration

Administration of drug to the therapeutic target site or absorption site in the nasal cavity is the first step in nasal drug delivery. Uniform distribution over the affected area is desirable for the treatment of nasal symptoms, whereas targeting of the favorable absorption sites... 

In addition, the most popular view of nasal drug delivery is the administration of locally acting products. Topical decongestants or anti-inflammatory drugs used to treat a rhinitis or allergy related indications are well-known drug products. They expand their effect directly at the focus of the disease. 

As mentioned previously, one of the major benefits of nasal drug delivery is the rapid onset of action (tmax)- Migraine treatment takes advantage of this fact. Compared to the orally taken tablet, tmax is much shorter. The neurosecretory hormone melatonin, which is used widely against jetlag, shows a very impressive time profile when administered as a nasal spray. The peak levels of melatonin after nasal administration appear to be 50 times higher than after oral administration. 

Nasal sprays may also be used to achieve a systemic effect. Intra-nasal drug delivery provides a speedier onset of drug action when compared with oral administration, often with a reduced dosage. Examples include ... 

Desmopressin may be given orally, intranasally, SC, or IV. The oral dose must be determined for each individual patient and adjusted according to the patient s response to therapy. When the drug is administered nasally, a nasal tube is used for administration. The nasal tube delivery system comes with a flexible calibrated plastic tube called a rhinyle. The solution is drawn into the rhinyle. One end is inserted into the nostril and the patient (if condition allows) blows the other end to deposit solution deep into the nasal cavity. A nasal spray pump may also be used. Most adults require 0.2 mL daily in two divided doses to control diabetes insipidus. The drug may also be administered via the SC route or direct IV injection. 

Educating the Patient and Family If lypressin or desmopressin is to be used in the form of a nasal spray or is to be instilled intranasally usingthe nasal tube delivery system, the nurse demonstrates the technique of instillation (see Fhtient and Family Teaching Checklist Self-Adnrinistering Nasal Vasopressin). The nurse includes illustrated patient instructions with the drug and reviews them with the patient. If possible, the nurse lias the patient demonstrate the technique of administration. The nurse should discuss the need to take the drug only as directed by the primary health care provider. The patient should not increase the dosage (ie, the number or frequency of sprays) unless advised to do so by the primary health care provider. 

Parenteral administration is not perceived as a problem in the context of drugs which are administered infrequently, or as a once-off dose to a patient. However, in the case of products administered frequently/daily (e.g. insulin to diabetics), non-parenteral delivery routes would be preferred. Such routes would be more convenient, less invasive, less painful and generally would achieve better patient compliance. Alternative potential delivery routes include oral, nasal, transmucosal, transdermal or pulmonary routes. Although such routes have proven possible in the context of many drugs, routine administration of biopharmaceuticals by such means has proven to be technically challenging. Obstacles encountered include their high molecular mass, their susceptibility to enzymatic inactivation and their potential to aggregate. 

The nasal route of drug delivery is used for the direct administration of medicines to the nose for treatment of local conditions or the systemic delivery of compounds that are not easily delivered by the oral route. It is also suggested that there may be a direct route for drug absorption to the central nervous system (CNS) from the olfactory region of the nose. 

Nagai, T., and Y. Machida. 1990. Bioadhesive dosage forms for nasal administration, in Bioadhesive drug delivery systems, eds. V. Lenearts, and R. Gurny, 169. Florida CRC Press, chap. 9. 

Due to the lack of activity after oral administration for most peptides and proteins, administration by injection or infusion - that is, by intravenous (IV), subcutaneous (SC), or intramuscular (IM) administration - is frequently the preferred route of delivery for these drug products. In addition, other non-oral administration pathways have been utilized, including nasal, buccal, rectal, vaginal, transder-mal, ocular, or pulmonary drug delivery. Some of these delivery pathways will be discussed in the following sections in the order of the increasing biopharmaceutic challenges to obtain adequate systemic exposure. 

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