Because we are having low blood sugar at night, our doctor recommended that we use Lantus. One year ago, she told me that I can’t mix Lantus with Humalog. Now she recommended a dinner time mix of 2 1/2 units of Humalog and 4 1/2 units of Lantus. I am a little bit confused, because I read that Lantus cannot be mixed. I need a second opinion.

According to sanofi-aventis, the maker of Lantus, Lantus should not be mixed with any other insulin. However, many clinicians have discovered that their patients are mixing Lantus with rapid acting insulin analogs, such as NovoLog and Humalog, even though they’ve been told not to.

At the 2005 Scientific Sessions of the American Diabetes Association, there was an abstract that deals specifically with your question:

“In Mixing Rapid-acting Insulin Analogs with Insulin Glargine in Youth with Type 1 Diabetes,” a team of researchers from the Barbara Davis Center in Denver reported on a six-month study of 55 kids with type 1 diabetes who mixed Lantus with a rapid acting analog (NovoLog or Humalog) and compared their blood sugar control with 55 kids who did not mix. Their data showed no significant differences in HbA1c; percentage of blood sugar readings in, above, or below a target range; nonsevere and severe hypoglycemia; or episodes of DKA. In summary, the ream concludes that mixing Lantus with a rapid acting analog had no effect on blood sugar control and doing so results in fewer daily injections, possibly offering kids an easier diabetes regimen.

JSH