GPs feel under pressure to use generic drugs even though many feel it interferes with patient care.
In a survey carried out by Pulse magazine, of 401 GPs polled, two thirds said they felt under pressure to prescribe cheaper drugs and a third said this had interfered with care.
The government has encouraged local health bosses working for primary care trusts to get GPs to rely on generic drugs where it is appropriate.
As well as quizzing GPs, Pulse asked PCTs what they were doing to get doctors to use cheaper drugs.
Nearly all said they had schemes in place ranging from simple awareness raising campaigns to bonuses for hitting targets. Programmes to increase generic statin prescriptions remained the most popular, but others to target blood pressure drugs ACE inhibitors, antihistamines and antiplatelet drugs to prevent blood clots have also become more common in the last year.
Dr Richard Vautrey, deputy chair of the BMA's GP committee, said GPs felt caught between the "devil and the deep blue sea" over the issue.
"There is certainly logic in trying to save the NHS money, but the pressure is becoming intense."
But Department of Health spokesman said: "Cost-effective prescribing releases resources for more patients to receive treatment.
"However, we expect GPs to exercise their clinical judgment to ensure that their patients are prescribed the most suitable product available. There is nothing to prevent branded prescribing if a doctor considers it in the patient's best interests to receive a specific product."