DexCom (DXCM 1.51%) is a healthcare company that makes continuous glucose monitoring (CGM) devices, which help people track glucose levels.

However, the rising popularity of GLP-1 drugs, which are highly effective in helping people lose weight and also reduce the risk of becoming diabetic, has turned some investors bearish on DexCom's business. If people are slimmer, healthier, and less likely to become diabetic, there would seemingly be less of a need to use CGMs.

There's some uncertainty as to how the business will do in the future, and while the stock has struggled over the past year, it has been picking up steam of late, rallying more than 20% in three months. With its latest earnings report coming out on Feb. 13, is it a good idea to buy the healthcare stock before then?

DexCom's slowing growth a potentially big concern for investors

There's been a huge drop-off in DexCom's growth rate of late, and that's a key reason investors believe that there may be a strong correlation between rising GLP-1 use and demand for CGMs.

DXCM Operating Revenue (Quarterly YoY Growth) data by YCharts

The company slashed its forecast last year, blaming a restructuring of its sales team as a reason for the decline in its growth rate. Investors, however, may be skeptical about that playing such a huge role in its ability to grow its revenue.

The question marks and uncertainty about that is a reason why it might be better to wait until after DexCom reports earnings before making a buying decision, to see if its business is showing signs of improvement.

DexCom's stock is down nearly 30% in the past year, but is it cheap?

Shares of DexCom have been gaining momentum in recent months, but they still haven't recovered from the sell-off they went on last year after the company posted poor results and reduced its guidance. Investors may still see an opportunity to buy the healthcare stock at a more favorable valuation today. It is, after all, trading at a much lower price-to-earnings multiple than what it has historically averaged in the past.

DXCM PE Ratio data by YCharts

Investors have been willing to pay a premium for the business due to the opportunities in the diabetes market. But if there are fewer people who potentially need CGMs due to GLP-1 weight loss drugs, that is certainly a reason investors may want to lower the price they are willing to pay for the stock. And at more than 50 times its trailing earnings, the stock still looks incredibly expensive.

Should you buy DexCom stock today?

I'm bullish on DexCom's future because while GLP-1 drugs are taking off today, people may not be able to afford to stay on them forever; these are drugs that need to be taken on an ongoing basis, and stopping them could result in people regaining the weight they lost. This is why although demand for DexCom's business could feel the (negative) effects of this GLP-1 excitement and hype in the short term, I don't believe it'll drastically hurt its outlook in the long run.

If you're in it for the long haul, then investing in the business right now may not be a bad move. There is the potential that the upcoming earnings results could be underwhelming again and there may be a decline in the share price; however, in the long run, there are still significant opportunities ahead for DexCom. Years from now, buying at today's price could look like a steal of a deal.