"They have increased production of some product lines three times in response to Covid," he said.
"I know they have been prioritising product to where it is needed most, not just filling every order, but filling orders that are actually going to patients."
And, with F&P Healthcare's products only reaching 10 per cent of the addressable market, there was still potential for further growth ahead.
The strong performance on the local bourse was underpinned by Wall Street bouncing back from Friday night's sell off. US investors were again "buying the dip" in hopes of further monetary stimulus supporting the economic recovery.
"The positive lead overnight from Wall Street showed there was still cash out there and people that are willing to put money to work on dips," Trethewey said.
That upbeat sentiment encouraged investors to buy risker stocks that have been underperforming in recent days as the resurgence of new Covid-19 cases dampened moods.
Fletcher Building rose 4.8 per cent to $3.70 after saying it would make an early repayment of US$300m ($467.5m) of its most expensive debt, USPP notes. That will reduce its funding costs by $17m per year, and still leave the company with $1.1b of liquidity.
Air New Zealand rose 4.8 per cent to $1.32 and Auckland International Airport advanced 2.2 per cent to $6.57.
Kathmandu Holdings snapped a three-day decline, rising 3.7 per cent to $1.13.
The dual-listed lenders also gained ground. Westpac Banking Corp rose 3.1 per cent to $19.40 and Australia and New Zealand Banking Group increased 2.4 per cent to $20.15.
Oceania Healthcare increased 3.5 per cent to 90 cents, Metlifecare rose 2.2 per cent to $5.14, Ryman Healthcare advanced 2 per cent to $13.08 and Summerset Group Holdings climbed 1.6 per cent to $6.46.
Among blue chip stocks, A2 Milk Co rose 2.2 per cent to $20.19 and Spark New Zealand was up 1.8 per cent to $4.56.
Meridian Energy fell 2.6 per cent to $4.81 after the Electricity Authority said the country's biggest electricity generator potentially created an 'undesirable trading situation' that cost consumers as much as $80m.
SkyCity Entertainment posted the day's largest drop, falling 4 per cent to $2.39 in the stock's fifth straight decline. Vista Group International dropped 2.7 per cent to $1.45.
Outside the benchmark index, Cooks Global Foods fell 5 per cent to 5.7 cents after it said it didn't expect trading at its cafe franchises to return to normal until the second half of the 2021 financial year.