Patients want to discuss complementary medicine with GPs but many do not as they are embarrassed, research shows.
Complementary therapies can be dangerous
Some 71% said they want to talk about therapies such as hypnotherapy and herbal medicine with pharmacists or doctors, a poll of 1,000 people showed.
But 38% said they felt most doctors disapprove of the use of such medicine, according to health education charity Developing Patient Partnerships (DPP).
DPP said GPs needed to offer patients advice on complementary treatment.
Dr Terry John, spokesman for the charity, said: "Patients and health professionals are crying out for more information on complementary medicine.
"It is crucial that health professionals have information to hand when necessary, and likewise patients need the necessary information to make informed choices about their treatment."
But a separate poll of 100 GPs found only just over half (52%) of family doctors routinely asked patients about their use of complementary medicine, with 47% saying they believed they should not be the ones providing information and advice on the subject.
Some 85% said they did not have enough information about the safety and efficacy of complementary medicines.
The complementary medicine market has been growing in recent years.
Britons spend £130m a year on alternative therapies such as acupuncture and reflexology and that is expected to rise by £70m over the next four years.
DPP has now launched a new campaign - Talking About Complementary Medicine - as part of Ask About Medicines Week to provide more information on the subject and encourage communication between doctors and patients.
Michael Fox, chief executive of The Prince of Wales's Foundation for Integrated Health, set up to promote the integration of complementary medicine into mainstream treatment, said: "Complementary and conventional medicine can work safely alongside each other as long as there is effective communication between all practitioners as well as between patients and practitioners.
"For patients to receive the best treatment, it is essential to make sure that complementary practitioners are aware of any conventional treatment they are having and that other health professionals are aware of any concurrent complementary treatments."
Dr Michael Dixon, chairman of NHS Alliance, added: "Patients should not be forced into an either/or situation.
"Orthodox medicine must accept that an increasing number of patients choose to use complementary therapies.
"That means doctors need to learn more about them, and discuss the benefits and disadvantages with their patients."
But Dr Jim Kennedy, prescribing spokesman for the Royal College of GPs, warned complementary therapies were a "broad church" and should not a replacement for traditional medicine.
"Some of it has an evidence base, some of it doesn't and some is quite frankly dangerous.
"As doctors, our first priority is always to protect the health of our patients"