Operating expenses in the second quarter of 2024 increased $2.0 million, or 4%, to $48.3 million, compared to $46.2 million in the second quarter of 2023.
Operating income was $5.8 million in the second quarter of 2024, compared to $2.1 million in the second quarter of 2023. Non-GAAP operating income in the second quarter of 2024 was $6.5 million, compared to $3.6 million in the second quarter of 2023.
Other income was $0.2 million in the second quarter of 2024, compared to other expense of $0.8 million in the second quarter of 2023.
Income tax expense was $1.8 million in the second quarter of 2024, compared to $1.3 million in the second quarter of 2023.
Net income in the second quarter of 2024 was $4.3 million, or $0.18 per diluted share, compared to a net loss of $0.1 million, or ($0.00) per diluted share, in the second quarter of 2023. Non-GAAP net income in the second quarter of 2024 was $4.8 million, compared to $1.0 million in the second quarter of 2023.
Weighted average shares used to compute diluted net income (loss) per share were 24.1 million and 23.4 million for the second quarters of 2024 and 2023, respectively.
Adjusted EBITDA was $9.1 million in the second quarter of 2024, compared to $6.1 million in the second quarter of 2023.
First Six Months 2024 Financial Results
Total revenue for the six months ended June 30, 2024, increased $7.1 million, or 6%, to $134.3 million, compared to $127.2 million for the six months ended June 30, 2023. The increase in total revenue was attributable to an increase of $7.2 million, or 7%, in sales and rentals of the lymphedema product line, slightly offset by a decrease of $0.1 million, or 1%, in sales of the airway clearance product line for the six months ended June 30, 2024, compared to the six months ended June 30, 2023.
Net income for the six months ended June 30, 2024, was $2.1 million, or $0.09 per diluted share, compared to a net loss of $2.0 million, or ($0.09) per diluted share, for the six months ended June 30, 2023. Non-GAAP net income for the six months ended June 30, 2024, was $3.5 million, compared to $0.4 million for the six months ended June 30, 2023.
Weighted average shares used to compute diluted net income (loss) per share were 24.1 million and 22.3 million for the six months ended June 30, 2024 and 2023, respectively.
Adjusted EBITDA was $10.1 million in the six months ended June 30, 2024, compared to $6.6 million in the six months ended June 30, 2023.
Balance Sheet Summary
As of June 30, 2024, the Company had $73.6 million in cash and cash equivalents and $27.8 million of outstanding borrowings under its credit agreement, compared to $61.0 million in cash and cash