Dozens of common treatments to help with a range of ailments are of little or no use, senior doctors have said.
To help patients and medics make the right decisions about care, the Academy of Medical Royal Colleges (AMRC) has recorded 40 treatments or tests with this in mind, along with the gentle warning that "more doesn't always mean better" - part of its Choosing Wisely UK campaign.
Using tap water to clean up cuts and grazes is just as good as a saline solution, and a plaster cast is not needed for some small wrist fractures in children who may find that a removable splint will help them to heal just as quickly, according to the AMRC advice from its medical royal colleges and facilities.
Another example is that X-rays do not help to deal with lower back pain if there are no other concerning features.
Lower back pain, prostate condition and terminal cancer are among the wide-ranging ailments which are also touched upon in this first wave of recommendations.
It comes after 82% of doctors said they had prescribed or carried out a treatment which they knew to be unnecessary in a study carried out last year.
Patient pressure or patient expectation was given as the main reason, the AMRC noted.
The global campaign aims to cut down on over-medicalisation and to help provide the groundwork for a fully-informed conversation about the risks and benefits of treatments and procedures.
The AMRC also gives key pointers to patients and doctors on how to treat health-related issues.
Patients should ask about the risks or downsides, the possible side effects, if there simpler or safer options, and "what will happen if I do nothing?".
The advice also notes that chemotherapy may be used to relieve terminal cancer symptoms, but can also be painful, cannot cure the disease and may well bring further distress in the final months of life.
Adrienne Betteley of Macmillan Cancer Support said: "It is vital patients are as well-informed as possible to help them make decisions around their treatment.
"Chemotherapy is a crucial part of cancer treatment, having had an enormous impact on rising survival rates over the years. However, it can result in severe side effects, therefore it's important that health care professionals consider the full impact when delivering something so powerful.
"It's also important cancer patients are told about potential side effects, be offered a care plan, be told where to get support and know who to speak to about their worries and fears.
"The NHS needs to be equipped to provide this for cancer patients in order to cope with the increasing numbers of people being diagnosed and living with the disease."
AMRC chairman Professor Dame Sue Bailey said: "We all have a duty to look after resources in healthcare, especially when the NHS is under so much pressure, but that's not the main motivation for this initiative.
"What's much more important is that both doctors and patients really question whether the particular treatment is really necessary. Medicine or surgical interventions don't need to be the only solution offered by a doctor and more certainly doesn't always mean better".
Professor Maureen Baker, chair of the Royal College of General Practitioners, hopes the guidance will enable GPs to focus on patients who really need their help.
"At a time when patients in some areas of the country are having to wait for nearly a month to see their GP - due to rocketing demand and not enough GPs to keep pace - this report is a dose of common sense.
"The guidance shows there are many minor ailments and conditions that can be treated quickly and effectively without needing to see a GP, meaning that family doctors can dedicate their valuable time to those patients who really need our expert skills.
"As well as demonstrating to patients why going to the GP isn't always the best course of action, it should also reduce the pressure on GPs to prescribe medications such as antibiotics which might not be needed."