The Swiss interior minister, Ruth Dreifuss, has warned that a proposal to promote cheap medicine would threaten public health and undermine international trade rules. The issue is due to go to a nationwide vote in March.
Dreifuss said on Friday that the initiative would threaten public health, infringe international trade rules and restrict doctors' rights.
The initiative is aimed at restricting health insurance coverage to the cheapest medication available on the market. It also demands that medicines already on the market in Switzerland be made available for sale to neighbouring countries.
Dreifuss, who also holds the health portfolio, warned that if the proposal was approved by voters many patients with chronic illnesses would suffer because they would frequently be forced to change their medication.
She said the initiative would favour certain countries at the expense of others and lead to surfeit of medicines on the Swiss market, which is subject to cartel restrictions.
The initiative was launched by the founder of a nationwide retail chain, Denner, in 1997. His supporters collected more than 120,000 signatures to force a nationwide vote on the issue.
The government and parliament have come out against the proposal, saying it breaches international regulations and threatens public health standards.
The initiative is the latest in a series of proposals to cut spiralling health costs. Health insurance premiums have been rising steadily in past few years.
Last year, Swiss voters rejected a proposal to limit mandatory insurance coverage to hospital stays.
swissinfo with agencies