A common misconception is that you need a lot of money to invest in the stock market. However, even a small amount is enough to start. With the right stocks, a small investment can grow greatly in value. Some growth stocks have the potential to deliver massive returns as long as you have a little patience and a reasonable risk appetite.

The healthcare industry is both risky and defensive. People will continue to fall ill regardless of the economic situation. As a result, demand for healthcare products will never decline. At the same time, not all potential medications make it to the market. 

Let's look at three healthcare stocks that can be purchased for $100 and have good prospects to grow over time.

Axsome Therapeutics

While most growth stocks struggled in 2022, Axsome Therapeutics' (AXSM 1.54%) shares increased by 104%. The stock hasn't been off to a great start this year, dipping 18%, but the odds look pretty good for the company in the near future. This biotech has two promising new drugs in its portfolio.

In May, the company purchased Sunosi from Jazz Pharmaceuticals. This medication, which is used to treat narcolepsy-related excessive daytime drowsiness, is the company's best-selling product. The drug generated $19.2 million in net sales in the U.S. during 2022's fourth quarter.

Auvelity, another of its products, debuted in the U.S. this past October. This medication is prescribed to treat depression or major depressive disorder (MDD). In the fourth quarter, it made $5.2 million in net sales. Since the pandemic, the diagnosis of MDD has increased dramatically. This drug has the potential to be a game changer for Axsome. Axsome's revenue could skyrocket once both drugs are available in international markets. Sunosi has already begun selling in a few international markets as of November 2022.

Axsome is investing heavily in research and development to expand its portfolio, which totaled $58 million in 2022. The company's pipeline is full of exciting potential products. AXS-05 is intended to treat MDD, smoking cessation, and agitation in Alzheimer's disease. A clinical trial is currently in its second phase.

More in the pipeline -- AXS-07 for migraine treatment, AXS-12 for narcolepsy treatment, and AXS-14 for fibromyalgia management -- could be enticing prospects for the company once they hit the market. Financially, the company is strong enough to support its pipeline advancement. At the end of the fourth quarter, it had $201 million in cash.

The company's financial resources are adequate for funding its current and future pipelines. At the end of the fourth quarter, it had $201 million in cash. Management believes that "its current cash, along with the remaining committed capital from the $350 million term loan facility" will be sufficient to cover projected pipeline progress.

AbbVie

Investors became cautious about AbbVie's (ABBV 1.22%) stock after its star drug Humira lost patent exclusivity in the U.S. at the beginning of 2023. The drug is prescribed to adults who have moderate to severe rheumatoid arthritis. In 2022, it generated $21 billion in sales, accounting for 36% of AbbVie's total revenue.

Humira sales in the U.S. are projected to drop by 37% in 2023, according to the management. Humira has been the biotech company's most successful product. However, AbbVie is wise to not rely on a single product to thrive. Its portfolio includes several other successful drugs.

Rinvoq (used to treat moderate to severely active rheumatoid arthritis in adults) and Skyrizi (used to treat moderate to severe plaque psoriasis in adults) are two of its other promising drugs. Management believes that these two drugs will eventually outsell Humira by 2027. Both drugs generated $7.6 billion in sales for the entire year 2022.

The company continues to make significant investments in research and development, which totaled $6.5 billion, or 12% of revenue, in 2022. Though the short term looks difficult for AbbVie until it compensates for the loss of Humira, the company's long-term prospects are bright.

An additional benefit is that AbbVie is also a dividend-paying stock. It has earned the title of Dividend King by raising dividends for 51 consecutive years (including its time at Abbott Laboratories, which spun it off in 2013). AbbVie's dividends have increased by more than 250% since the spinoff. It is a credible growth and income stock due to its consistent dividend payments and a strong portfolio of effective drugs.

Even a small investment in these growth stocks, combined with a diversified portfolio of stable stocks, would be a wise long-term move.