I Am Having Great Success With My Dexcom

It took me three weeks to have this success but it is going very well now. Thanks to Rick and others here who helped. One member sent me emails and helped a lot. I wonder why some of the best suggestions I received are not in the Dexcom manual? Rick posted some very good tips and my email friend gave some very good ones too. My numbers now agree with my meter so well that I can reduce the number of finger sticks. I still use finger sticks for all boluses and my fasting and bedtime testing.

any chance you could post all those tips?

Yes, I will post tomorrow. It is 11 PM now and i cannot think straight. LOL!

Congratulations Richard, I’m glad to hear that you have been successful. I have been using Dexcom for a month or two and have become somewhat addicted to checking my bg. There are still times that it goes off, but they are becoming somewhat obvious. For instance when I feel low, I usually am low regardless of what Dex has to say.
Good luck - Allen

I have been on my Dex 7+ for about 3 months and I love it. I am becoming addicted to pushing the button to see what my reading is. My numbers are almost always within 5 points of my fingerstick. Thanks to the CGM I have made some basal rate changes and now hardly ever have the alarm go off in the middle of the night. When I first started on the Dex it was going off constantly at night. A good 8 hours worth of sleep makes it soooooo worth all the trouble I had to go through to get it. I cant imagine life without it now.

For those of you who wanted to see the useful tips I have learned from more experienced Dexcom users, here is a thread that gave me some very good info:


My email friend gave me the tips listed below. Some of them are also in the thread posted above.

1.) Enter BG’s only when less than 10 points from meter reading.
2.) Wait at least 6 hours after putting new sensor and transmitter in place before starting up.
3.) Start up when the meter BG’s are good and near the center of your range. Also start when you are not stressed or going to experience a lot of physical activity.
4,) Place sensors in the center region of your abdomen, but not too close to your navel. Do not place a sensor where you might sleep on it .
5.) Keep the receiver out of the bath room when there is a lot of dampness present.
6.) The transmitter may have popped out of place when the numbers are crazy. If so, pop it back into place.

We have been advised not to place sensors on body parts where there is scar tissue present. I have permanent scar tissue on my upper ab from 61 years of injections. I use my lower ab for sensors.

My email friend also says not to use tape over the sensor tape to hold it in place. She thinks moisture will collect if you do that. (I am not sure about this one. The manual shows four strips of tape being used. I use two.)
She says to not push the sensor beyond seven days. (I am not sure about that one either. Several members here are getting good results after 7 days.)

I had my second sensor fail after only two days. I noticed that I had placed the sensor at a level where my belt was pressing tight against one edge of it. That may have bothered the sensor or transmitter, or both of them and the failure occurred. My infusion set is not bothered by pressure like that but the transmitter/sensor combo certainly seems to be.

I have been advised to not enter BG’s except when the Dexcom calls for them. I do occasionally enter an extra one when I am 15-20 points above/below my meter reading. I think this helps more than it hurts, at least in my case. I try not to enter an extra number more than once each 24 hours.

I am using my fourth sensor since I started in the first few days of January. I have been within 10 poiints of my meter at least 80% of the time. That is very satisfactory, in my opinion.

Richard - Thank You for sharing your information with others who use the Dexcom 7+. Some of the tips I knew already, but other ideas were new to me. It is a good day when I learn something new. May you have continued success.

Thanks so much for posting these tips! I’m a new user, and they’re very helpful. But can you tell me why it’s best to wait 6 hours after sensor insertion? Is it still not giving accurate readings after 2 hours?

My email friend has waited as long as 12 hours after a new sensor insertion. She has more success with agreement between Dex and meter readings that way. Others here have suggested a six hour wait. I do not know why the wait helps, maybe someone can respond to that. I will make a wild guess and say that the transmitter and receiver might need some time to set up communication before good results are seen. The six hour wait might establish that communication before you start the new sensor. Otherwise, you might see wider gaps between Dex and meter results for several hours after starting. Does that sound reasonable?

The unreliable readings in the beginning are caused by the foreign body reaction. The immune systems reacts to the trauma caused by the sensor insertion. There is no way of telling when this first response dies down. It depends on your immune system, the time of day, what exact location you hit. In other words, the readings are just unpredictable in the beginning. I had sensors with good readings after 2 hours. My last sensor hit a blood vessel and took almost a day to quiet down.

Thanks RR, you have helped me a lot! My fourth sensor is working great, thanks to you. We went to a movie and depended on Dex instead of finger sticks and everything went very smoothly. I will never depend on Dex for bolusing.

P.S. In my childhood RR stood for Roy Rogers. Now RR is Rebel Rita. LOL!

Hi Rita, New to dexcom system and heard what u said about leave sensor sit for at least 8 hrs. Just so am clear (and maybe me being stupid) do u mean inserts sensor but dont attach transmittor or attach transmittor but just dont press start sensor on dexcom? Thanks, Chris

Yes Chris that’s exactly what she means. I attach a new sensor when I get the “Change Sensor Soon” warning. Then I restart the old one until it dies and switch to the new one. The first day or so is still not as reliable as later days with the same sensor, but it is an improvement. Allen

The “problem” with the Dexcom Manual is simple: it’s FDA-regulated and Approved, along with the device itself. Since Dexcom could not afford to test alternative sites, they can’t be presented. In the same way, each kind of “adhesive helper” they talk about using would have to be thoroughly tested against using the Approved Sensors in the Approved way. (Lots of test subjects, lots of control subjects, lots of documentation, and lots of MONEY.)

I disagree with a couple of those things.

After starting a new Sensor (during the first 48 hours of running time), it is desirable to add a few more bG readings than Dexcom asks for (using it’s ongoing 12-hour countdown). An Abbott-like schedule is better in the first couple of days. Local body tissue is reacting to the damage of the Dexcom shoot-in, and the behavior of the Sensor membrane and Glucose Oxidase reactant compound changes a lot during the first two days of use. I always make at least 4 entries during the first day, above and beyond the initial “double-entry” required by the startup. 2 or 3 extras on the second day.

It’s also important to keep these “early” entries spread over a range of at least 20-30 mg/dL – Dexcom can’t set both the slope and the intercept of the calibration curve without having a reasonably wide set of readings to work from. (If you want accurate alarms, you have to calibrate it with bG readings near your alarm points.) Don’t go too far above your “high alarm”, or calibrate below 70 mg/dL, just do calibrations with bG values which are “moderately” separated. If I’m having a lucky day, and all of the readings are too close together, I’ll eat a couple of sugar tabs without bolus coverage to create 30 mg/dL of separation in the values. (Be sure to wait at least 45 minutes measuring and entering that bG, though, because Dexcom will be late at following the bG rise.)

“Enter bG’s only when less than 10 points from the meter reading” makes no sense to me, either: When it’s off by twenty points, it’s off by 20 points! and needs to be told of the error. Instead, my rules are to only enter bG values when you have been up and around for at least 1/2 hour, and to be certain that the bG value is trustworthy. (During the night, you “confirm” an alarm by checking bG-- but if Dexcom is wrong, you don’t enter that bG as a calibration value. Just change your alarm settings for the rest of the night.) Entering a calibration value when you’ve been sleeping, and the Sensor is reading from “stale” ISF or maybe even squashed against the bed, could lead to worse results the following day.

Never, ever enter a calibration with “fresh food” on board, or with rising bG. Even a slight rise of bG, with the arrow still pointing “level” is absolutely no good. Enter only during truly level bG, or a very gentle drop, in which the indicator arrow still shows “level”.

Your “belt-pressed-it-in” episode and my “squashed against the bed” scenario are two examples of the same problem: The Sensor wire needs to be absolutely motionless within your subcutaneous tissue. No bending, no pulling-out, and no pressing-in of the wire can be allowed, ever.

If) you can become successful at keeping the pad and wire motionless past 7 days, it’s silly not to take advantage of the really great results you’ll be able to get for the next 3-8 days. (Even if you get Sensors for free, why create all that unnecessary tissue damage?) For me and many others, even day 3 is still never as good as days 8-11. But this depends on finding a great site, and preparing it well, and pressing in the adhesive pad carefully before performing the shoot in. The pad fabric needs to be pushed in firm, especially underneath the transmitter housing, but must not stretched anywhere. (It takes tools to do this right, not fat fingers.)

Joann, you have helped me very much. Thanks! I have a list of your suggestions and I refer to it frequently.

Danny, thanks for your comments. I hope you are finding the Dexcom to be as useful as I am. I also hesitated to pump and use a CGM. I guess we are both that way. Lol!

Using a Sensor for more than 7 days is “off-label”, and infection was the FDA’s primary concern. But people who aren’t wealthy, and don’t have really good insurance coverage, sometimes find themselves having to make a choice between running it for extra days OR having many days with no CGM coverage at all. Since it might work even better on days 8-11 than it worked on days 1-2, that’s not a hard choice to make.

Or people like me, slow to heal and capable of professional-level cleaning techniques, find the minimal increase in infection risk to be a much better choice than the tissue damage caused by lots of unnecessary extra insertions.

I have described (elsewhere) my recommendations for proper site cleaning; and if you search the Internet for research literature on the subject, you will find that my “aggressive soap” recommendation has been found to be superior to the quick and lazy alcohol wipes widely used by nurses at vaccination clinics, and used by other people. The “skin prep” wipes which I use and dry twice, via hair dryer, contain considerable alcohol content too, and have similar killing action. But real cleaning is best done via my “aggressive soap scrub”, followed by an equally aggressive drying scrub: with totally fresh, not yet used for anything washcloths at both steps.

I’ve not yet bought or used PVI pads as a disinfectant for Dexcom sites. (That’s the red stuff, used in ERs and operating rooms). Maybe they’re OK to use; maybe they’re not OK, destroying Sensor accuracy/reliability. But I’ve never had signs of infection at any Dexcom site using the less effective “Skin Prep” and IPA pads after my aggressive scrubbing, so I probably won’t ever upgrade my process to the higher level. Infection risk is really a question of cleanliness, and much less a question of time. If the insertion area is truly clean, and no infectious agents are present to take advantage of the piercing, infection will not occur. The FDA time limit reduces the festering of infections which were already started, so that they clear up more easily (after they’ve been discovered and the wire stops hurting neighboring body tissue, and spreading the infection around). But, if you do it right, an infection will never start in the first place.

If a site becomes itchy or painful, you need to rip it out immediately. I HAVE had infected infusion sites in the past, when I was less careful about scrubbing my skin before inserting these skin-piercing appliances. Infections will often provoke pain or itch as part of the IR, and you should always remove the appliance when you experience either of these warning signs.

Please stop screaming in caps, you’re better than that.

Richard, I just discovered your post regarding your CGM congrads! I temparily wore one last year. I found it interesting because at that time I was suffering lots of lows. I’m waiting for Medicare to approve cgms and then I know that my suppllemental insurance will aprrove it. I’m not sure if I would like to wear it every day but I have yet to get it approved. I wish you well…isn’t it amazing the technology that helps us to see things clearer then years ago in those dark ages.

I APOLOGIZE TO EVERYONE, but especially RR and Richard157, for turning much of this Thread into a bunch of finger-pointing about “who knew it first”. Thank God, the worst parts of my screaming occurred within private messages… but I’ve also provoked some replies within the Thread.

Please, PLEASE ignore the mess I created. Richard157 has learned valuable things from MANY members, and has done a great job of writing them up into concise, well-organized posts. (My rambling posts are always far more difficult to read). Richard157 has thanked both Rita and myself many times, for “Everything”, and that should be enough. It’s a forum, not a scientific journal where every “borrowed” idea needs a footnote.

Again-- it’s my mess, and I’m taking blame for it. I’m very sorry to have done all those nasty PMs, and to whine about capitalization (and my God, in a public post!) Please, let’s get back to Dexcom and the cool tricks to make it work better.