Facebook shares took a 24 per cent plunge in after-hours trading after the social media giant revealed slower-than-expected user and revenue growth.

The company's shares fell to $201.40 in trading, wiping more than $150 billion off its value. This is Facebook's first full quarter since the Cambridge Analytica privacy scandal.

Facebook had 2.23 billion monthly active users at the end of June, which was an 11 per cent increase from June 2017, the slowest growth in more than two years.

Total expenses in the second quarter soared to $7.4 billion, a significant rise of 50 per cent from 12 months ago.

The social media firm warned investors that revenue growth would slow in the second half of the year and that expenses would grow faster than revenue next year as the company looks to address concerns about users' privacy.

Total revenue for the quarter grew by 42 per cent to $13.23 billion.

David Wehner, chief financial officer, said: "Our total revenue growth rates will continue to decelerate in the second half of 2018, and we expect our revenue growth rates to decline by high single-digit percentages from prior quarters sequentially in both Q3 and Q4."