Health chiefs have admitted they have faced “challenges” in treating the number of patients turning up at A&E in recent weeks.
Slips, falls and flu were blamed for the poor results in meeting waiting time targets.
Latest figures show that for the week ending December 10, 199 patients were not seen within the four hour target. Of these, 50 waited over eight hours and two waited over 12 hours.
The week before 250 patients failed to be seen within the four hour guidelines, the worst figure so far for 2017.
Officials from NHS Forth Valley said in the past two weeks, as well as a rise in the number of seriously ill patients being brought to its emergency department, slips, trips and falls during the icy weather, along with an increase in flu cases, had all played a part in the delays.
However, a spokeswoman said people can put pressure on the service by turning up at the Forth Valley Royal A&E rather than going to the minor injuries unit at Stirling Community Hospital.
Only 83.4 per cent of cases were seen within four hours when the target is 95 per cent.
A spokeswoman for NHS Forth Valley said: “We have experienced challenges in meeting the four hour A&E waiting time target over the last few weeks due to a number of factors. These include a rise in the overall number of attendances and an increase in the number of seriously ill patients who required to be admitted.
“We are continuing to do everything possible to reduce delays and all patients who attend our emergency department are seen and assessed to ensure patients with more urgent or serious health issues are prioritised. In many cases, patients will undergo tests and start treatment while they wait to admitted or discharged.
“People can also help reducing pressure on the emergency department at this busy time by only attending if they have a serious illness or injury which requires urgent attention.
“We would also encourage people to make use of local pharmacy and Minor Injuries Unit services which can provide fast treatment and advice for a wide range of common health problems.”
Health Secretary Shona Robison admitted that “pockets of the country had experienced increased attendance at A&E departments because of flu, respiratory illness and more slips and trips.
She said: “What remains a constant is the dedication of staff across Scotland’s healthcare system who should get the praise they rightly deserve for their hard work.
“Boards are working hard to mitigate against the biting effects of winter.”
Details of local health services available over the festive period are available at www.nhsforthvalley.com/winter.