Today may be a day known for ghouls and goblins, but it's been a downright frightening month for the stock market as a whole. So far this month, the broad-based S&P 500 and tech-heavy Nasdaq Composite have dipped into correction territory (defined as a drop of 10% or more from a recent high). This has included a handful of all-time top-10 single-session point losses.

More importantly, we could be witnessing the beginning of a shift from growth stock investing to value stocks. After all, we're nearing the 10th year of this economic expansion, and no matter what the Federal Reserve or U.S. government does, nothing can prevent an eventual economic contraction or recession. As interest rates rise and slowly close the door on "cheap" money, the proposition for value stocks continues to grow.

Meanwhile, some previously popular growth stocks may soon find themselves looking rather ghoulish. In the spirit of Halloween, consider the following three growth stocks more trick than treat.

A carved pumpkin with a devious face.

Image source: Getty Images.

Tilray

Marijuana stock Tilray (NASDAQ:TLRY), which only became a public company in July, has been an easy stock for growth investors to love. After all, Canada becoming the first industrialized country to legalize recreational cannabis on Oct. 17 paves the path for $5 billion or more in added annual sales once the industry is fully up to speed.

However, Tilray's low tradable float, combined with the company still being well within the lockup period, created a unique situation that allowed a short-covering rally to push its shares from $25 to $300 in a month. At a peak valuation of $28 billion, Tilray briefly stood taller than established companies like Hershey and American Airlines Group. Now the company has big shoes to fill with a mammoth valuation, and I highly doubt it'll be able to do so.

Although Tilray's prospectus calls for more than 850,000 square feet of completed capacity by the end of the year, this'll likely only put Tilray on pace for, say, 75,000 kilograms of annual production. Meanwhile, the larger producers, like Aurora Cannabis and Canopy Growth Corp., which bear similar valuations to Tilray, are probably going to produce more than 600,000 kilograms and around 500,000 kilograms, respectively, when at full capacity. Tilray isn't even in the same ballpark.

Making matters more worrisome, Tilray is going to be spending aggressively to boost its capacity and lay the foundation for its international infrastructure in the years that lie ahead. While this is very much needed for Tilray's long-term success, it almost assures that costs will exceed sales over the next couple of years. If the stock market continues to falter, investors simply aren't going to tolerate bloated losses and inflated share counts from pot stocks like Tilray.

A measuring tape being held around a person's waist.

Image source: Getty Images.

Medifast

Unlike marijuana stocks, which have been the talk of the town, you might be surprised to learn that weight-loss service companies like Medifast (NYSE:MED) have also been on fire. Shares of Medifast have tripled over the last eight months, with sales of its Optavia-branded products soaring.

During the company's second quarter, Medifast reported a 55% increase in year-over-year sales to $117.3 million, along with a 46% jump in active-earning coaches to 19,700. Most important, net income increased 86% to $14.1 million, allowing Medifast to increase its full-year sales and profit guidance by about 20% on both accounts. So what's wrong? 

Arguably the biggest issue with weight-loss service providers is that they're expendable when economic growth slows. Medifast has enjoyed success because the unemployment rate is low and wage inflation is picking up. In essence, consumers have had the disposable cash to eat better and pay for services that could help them lose weight and live healthier lives. But, as we know, this economic expansion isn't going to last forever; and when it does falter, Medifast will be among the first stocks to fall.

Looking back through the company's past 15 years, it's had three separate instances in which its stock has skyrocketed in value only to lose more than 80%, roughly 75%, and more than 50% of its value in the subsequent years. Consumers are highly fickle with their disposable income, and Medifast is simply not a stock that can continue to be valued at 61 times trailing 12-month earnings per share.

Two Tesla Model 3 cars being debuted.

Image source: Tesla Motors.

Tesla Motors

Lastly, there's electric vehicle (EV) giant Tesla Motors (NASDAQ:TSLA), which has put its pedal to the metal and defied short-sellers for years despite extensive losses.

CEO Elon Musk is the first person to successfully introduce a new car brand in decades, and investors appear to be sold on the idea that Tesla can compete with the big boys while maintaining clear competitive advantages in terms of production efficiency, cost, and EV range. The company's recently reported third-quarter results also included a surprising profit of $2.90 per share when a modest per-share loss was expected, as well as $1.39 billion in positive operating cash flow, having previously not generated in excess of approximately $500 million in operating cash flow in any previous quarter. 

But there are also a lot of liabilities to consider here. Some view CEO Elon Musk as an indispensable visionary for Tesla. I view him as the company's Achilles' heel. Musk's off-the-cuff tweets have resulted in personal and company-based monetary fines from the Securities and Exchange Commission. Not to mention, Musk doesn't exactly have the best track record at meeting profit and/or production estimates that he's offered. Thus, even when Musk says the company will be generating ample cash flow moving forward, I'd take that comment with a grain of salt.

There's also concern as to whether Tesla can hit its long-term margin target of 25% on the Model 3. It's certainly come close with the higher-priced all-wheel-drive model dominating third-quarter deliveries, but the cheaper Model 3 is likely to drive down margins and push Tesla further away from any chance of consistent profits and healthy operating cash flow in the near term.

Sorry, folks, but Tesla is more trick than treat right now.

Sean Williams has no position in any of the stocks mentioned. The Motley Fool owns shares of and recommends Tesla. The Motley Fool has a disclosure policy.