Salisbury Hospital has declared an 'internal critical incident' after several of its IT systems became unresponsive.
Teams across the site have implemented back-up plans, which has enabled the hospital to remain open.
However, patients are being asked to only attend A&E if they are experiencing a life threatening condition or serious injury.
The hospital is urging patients to use alternatives to A&E, including the Salisbury Walk in Centre and NHS 111 online and by phone.
The hospital says its IT team is working with contractors to fix the problem.
CEO Stacey Hunter said: "Our IT team have been working through the night and continue to work today in order to fix the problems.
"I am grateful to everyone at the hospital who have worked so hard to maintain services under very difficult circumstances.
"The impact of using back up plans has meant that some services have seen onsite waiting times longer than normal.
"I am incredibly sorry for the disruption and thank patients for their tolerance and understanding."
What other services can you use?
Urgent Treatment Centres
Urgent Treatment Centres
Urgent treatment centres (UTCs) are GP-led, open at least 12 hours a day, every day, offer appointments that can be booked through 111 or through a GP referral, and are equipped to diagnose and deal with many of the most common ailments people attend A&E for.
UTCs will also ease the pressure on hospitals, leaving other parts of the system free to treat the most serious cases. The UTC offer will result in decreased attendance at A&E, or, in co-located services offer the opportunity for streaming at the front door. All UTC services will be considered a Type 3 A&E.
A General Practitioner (GP) is your family doctor and is the main point of contact for general healthcare for NHS patients. All UK residents are entitled to the services of an NHS GP.
GPs are highly skilled doctors who support patients throughout their lives. They help you to manage your health and prevent illness and are trained in all aspects of general medicine. This includes child health, mental health, adult medicine, the diagnosis and management of acute medical and surgical problems and the management of long term health conditions.
GPs assess, diagnose, treat and manage illness. They carry out screening for some cancers and promote general health and wellbeing. GPs act as a patient’s advocate, supporting and representing a patient’s best interests to ensure they receive the best and most appropriate health and/or social care.
As qualified healthcare professionals, they can offer clinical advice and over-the-counter medicines for a range of minor illnesses, such as coughs, colds, sore throats, tummy trouble and aches and pains.
If symptoms suggest it's something more serious, pharmacists have the right training to make sure you get the help you need. For example they will tell you if you need to see a GP, nurse or other healthcare professional.
All pharmacists train for 5 years in the use of medicines. They are also trained in managing minor illnesses and providing health and wellbeing advice.
Many pharmacies are open until late and at weekends. You do not need an appointment.
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