The study, by ICM Research, found that this cynicism is even stronger in the older age groups, who are the largest users of drugs. Seventy-four per cent of over-65s agreed with the statement.
The finding will cause alarm among pharmaceutical comms chiefs. GSK's senior VP of global comms Phil Thomson said this data was 'not what we want to see'.
He added: 'Trust in how we operate is fundamental to GSK. It is why we have taken - and will continue to take - action to be open and transparent about our medicines.'
The research reflects one of the major controversies in the pharma industry over the past years - the issue of whether companies are sufficiently open about potentially negative side-effects of their products. GSK has been criticised on this front with regard to its Seroxat and Avandia drugs.