LAVAL, Que. -- Bausch Health Companies Inc. (BHC.TO) raised its guidance after higher sales at its biggest subsidiary mitigated the blow of a US$52-million loss in its first quarter.

Bausch & Lomb, a segment that generates more than half of the drug company's revenue, saw revenue rise eight per cent to US$1.12 billion, after adjusting for foreign exchange, divestitures and discontinuations, according to the company.

"Clearly the majority of the growth in our Bausch & Lomb franchise is driven by the volume," chief executive Joseph Papa said.

The Quebec-based company, formerly called Valeant Inc., increased research and development investment by about 30 per cent, part of Papa's shift away from an aggressive acquisition strategy and focus on returning to the black.

Bausch Health, which keeps its books in U.S. dollars, slashed debt by US$100 million in the first quarter, despite shelling out $195 million to acquire parts of Synergy Pharmaceuticals Inc., an American maker of gastrointestinal therapies that filed for bankruptcy under Chapter 11 in December.

The February deal was the company's first acquisition in more than three years since Valeant purchased Sprout Pharmaceuticals, the maker of a female sexual dysfunction drug, for about $1 billion, before selling it for next to nothing a couple of years later.

Bausch said its earnings loss amounted to 15 cents per share compared with a loss of $2.58 billion or $7.36 per share a year earlier.

Revenue totalled nearly $2.02 billion for the first quarter of 2019, up from nearly $2 billion in the first quarter of 2018.

On an adjusted basis, Bausch Health said it earned $358 million in its most recent quarter, up from an adjusted profit of $312 million a year ago.

In its outlook, the company said it now expects full-year revenue in a range between $8.35 billion and $8.55 billion, up from its earlier guidance for between $8.30 billion and $8.50 billion.

It also expects its adjusted earnings before interest, taxes, depreciation and amortization for the full year to come in between $3.40 billion and $3.55 billion, up from its earlier guidance for between $3.35 billion and $3.50 billion.

Bausch Health said its top 10 products grew organically by 11 per cent year over year in the aggregate last quarter.

Its shares were up more than six per cent to $33.38 in midday trading Monday.