Insulin Pumps

For most of the more than 30 years I’ve had type 1 diabetes, I’ve been at the mercy of a syringe. Up to four times a day, sick or well, working or on vacation, my body demanded insulin, and I gave myself an injection. Everything was planned around those four shots, including when and what I ate. Injections had to be made at about the same time each day, which meant that any change in my schedule always brought wild swings in my blood sugar.

A few years ago, all that changed. Gone were the daily injections and measuring of insulin. No, it wasn’t that my diabetes disappeared. (It never does.) What happened was that I started wearing an insulin pump.

Insulin pumps have been around for over two decades. They used to be bulky and awkward to manage, but today’s pumps are about the size of a beeper and designed for comfort. The syringe-like part holding the insulin is connected to a minicomputer that enables the wearer to precisely control insulin delivery. Unlike the injection system, in which insulin is given in larger amounts one to four times a day, a pump delivers a continuous low dose of insulin 24 hours a day and allows the wearer to program extra insulin to cover the rise in blood sugar after eating.

Here’s how it works: The pump can be placed outside your clothing or hidden inside. A very thin plastic infusion line runs from the pump into a tiny plastic catheter that’s inserted into your body somewhere — usually the leg or abdomen. When I put the pump in a pants pocket, for instance, I’ll run the barely noticeable connecting line over the waistband and insert the catheter into my leg. I don’t feel the device in my leg at all. In fact, pump wearers shouldn’t feel a thing.

Because the pump is programmed to my individual requirements, the insulin delivered is more precisely suited to my needs. Between meals and overnight, it feeds me the right amount of insulin to keep my blood glucose in the desired range. The pump delivery system is far closer to the body’s natural insulin delivery, which makes it easier to keep blood sugars under control.

A new kind of freedom

Initially, I was a bit of a skeptic. I’d already tried wearing an insulin pump almost two decades before, when the invention was in its infancy. In those days pumps were called autosyringes. They felt more like clunky mechanical devices than wonders of technology. To say that my first experience was a disaster would be an understatement. For one thing, the pumps were big and cumbersome. Imagine wearing what looked like a 1950s-style 5-by-8-inch transistor radio around your waist. The only way to hide it would have been to wear a tent.

It wasn’t just that it looked awful. Far worse, it didn’t always work. Sometimes it seemed to take on a life of its own, feeding out much more insulin than I had instructed it to, other times delivering less. Either I was hypoglycemic, and thus lightheaded and irritable, or — more dangerous — my blood sugar soared, leaving me unbearably thirsty and spaced out. At other times it simply wouldn’t work at all. After less than a month, I unbelted it from my waist and threw it onto a chair, never to put it on again.

So I was hardly enthusiastic when my new endocrinologist suggested I try an insulin pump. But I was willing to try anything to get my blood sugar under better control. I still didn’t believe it would work, and I didn’t want to be permanently attached to a machine, reminded every instant of my diabetes. But I also didn’t want to say no to a new doctor. I figured I’d wear it for a few weeks and then announce that it wasn’t for me.

Was I in for a surprise! To begin with, pumps these days are much smaller. They’re light and easy to wear, easily hidden in a pocket or undergarment. But most important of all, they work. In less than a week, I was hooked.

Like all diabetics who take insulin injections, I had been tied to a rigid schedule of insulin and meals. There was no flexibility in my eating schedule. If I woke up feeling fine but, say, had an upset stomach later in the day and didn’t feel much like eating, I still had to eat.

Now I have the kind of freedom that most people take for granted but that I once could only dream about. Because my pump delivers a background dose of insulin 24 hours a day, a late dinner or a late morning meal is now no longer a problem. I eat when I want, even skip meals if I’m not in the mood to eat.

Improved glucose control

And what I eat has also changed. With injections it was hard to make adjustments for a special meal or a treat. With the pump, I simply calculate the grams of carbohydrate I’m about to eat — the amount of carbohydrate in most foods is easy to find — and program the pump to deliver enough insulin to cover that amount. For example, for each 15 grams of carbohydrate I give myself one unit of insulin. Less guesswork, more precision. Best of all, since I started using my pump, my blood sugar control has greatly improved. My A1C level — the average of my blood sugars over three months — is down 25 percent.

As for my concerns that a pump would be a constant reminder of my diabetes, nothing could be further from the truth. Yes, it’s always attached to my body (although a disconnect mechanism lets me take it off for showering, intimate moments, or even trying on clothes). My pump has almost become an extra limb, so much so that I often forget it’s there. It is only when I change the infusion set that runs from the pump into my leg that I spend more than a few moments dealing with it. I need to change it once every three days or so.

The low-down on pumps

Is the pump for everyone who has diabetes? A study from the University of Alabama at Birmingham School of Medicine suggests that insulin pumps improve glycemic control even in patients who had previously controlled their blood sugar through taking multiple insulin shots each day. Despite my own hearty endorsement, however, the truth is that not every diabetic is a candidate for an insulin pump. Perhaps most important, pump users have to be motivated: Wearing a pump requires additional daily glucose testing. Because insulin pumps use short-acting insulin, any malfunction (usually clogged or kinked tubing) that impedes the flow of insulin can quickly result in a rise in blood sugars. If you’re not willing to test your blood sugar several times a day, the pump isn’t for you.

If you do decide to use an insulin pump, the model you choose is mostly a matter of personal preference. Six manufacturers sell them in the United States. They offer a 30-day trial period, so you can see if a given pump is for you before you make the commitment. Pumps cost $5,000 to $6,000, and insurance coverage varies. Some states have legislation mandating coverage for diabetic supplies, which may include pumps.

Today about 200,000 diabetics in the United States are registered users of insulin pumps, most of which have four-year warranties on parts and labor and a lifetime warranty on the motor. You can expect your pump to last at least five years. Some insurance companies will upgrade a pump. I’ve had my MiniMed pump for almost two years, and it’s been trouble-free.

Wearing a pump doesn’t mean you can forget you’re diabetic, but my insulin pump has definitely made life with diabetes much easier then it used to be.


Kanakis S. et al. The Business of Insulin Pumps in Diabetic Care: Clinical Economic Considerations. Clinical Diabetes. 20:214-216.

Joslin Diabetes Center. Not Quite asn Artificial Pancreas: Insulin Pumps and Glucose Sensor Devices.

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