Ellen Campbell -Grizzle

Persons living with diabetes have yearned for an alternative method to taking insulin by injection. Today, such a product has been developed and approved by the U.S. Food and Drug Administration (FDA) for adult use. Eighty four years after the first insulin injections were given, the drug can be delivered straight to the lungs.

The particle containing the insulin is small enough to get past the back of the throat and large enough so that it is not breathed right back out of the lungs into the air. Realistically, the product is appropriate for those with Type 1 diabetes who are on larger doses of insulin such as 60 or more units per day or those with Type 2 who can tolerate larger doses of the drug.

Take before meals

Pfizer's product (Exubera) is a short-acting, meal-time insulin in powdered form that you would take no more than 10 minutes before each meal. A long-acting insulin still needs to be given by injection with the product.

Once a capsule of the insulin is inserted into the inhaler, a trigger on the pump is squeezed to release the drug which appears in the form of a cloud in the inhaler. The Insulin is inhaled by drawing a regular breath. The product can be used to replace meal-time injections of rapid-acting insulin.

The inhalable insulin is an alternative to diabetes pills or may be used in combination with pills and longer-acting insulin for Type 2 diabetics. In all cases, blood glucose must be monitored regularly.

Potential side effects

The new inhaled insulin has limitations. First, you have to inhale a lot of insulin to get the amount that the body needs. Only a small amount of the inhaled insulin reaches the blood stream to lower the blood glucose. There are potential side effects associated with such a product. These include low blood glucose, dry mouth, chest discomfort and decreased lung capacity.

Inhaled insulin is not recommended for smokers or anyone who has smoked in the last six months. In these cases, almost twice as much of the inhaled insulin can enter the blood stream. This increases the possibility for overdosing. Persons with lung disease such as asthma, chronic obstructive pulmonary disease (COPD) and emphysema should not take this product. Long- term effects of delivering insulin by the lungs are to be studied.

In the pipeline

Scientists have been working on a number of new advances in insulin administration.

Buccal insulin: Efforts are being made to deliver insulin through the lining at the back of the mouth and throat. This avoids problems related to placing large amounts of insulin in the lungs. The problem is that a lot of insulin will be wasted in this process.

Oral delivery: Insulin taken as a pill is quickly broken down in the stomach and becomes useless in lowering blood glucose levels. Scientists are trying to package the drug by using special coatings or by altering the structure of insulin.

At this time, injected insulin remains an efficient way of delivering the drug. Non-injectable forms of insulin do waste a lot of the drug and can prevent problems related to dosage precision. They are also likely to be more expensive. However, for those who dislike needles they present a real option and adherence to treatment is likely to improve.

Ellen Campbell-Grizzle, president, Caribbean Association of Pharmacists; director, Information & Research, National Council on Drug Abuse; email: yourhealth@gleanerjm.com.