Typically, the Amphotericin B is well inhibits the growth of fungi with minor contamination and subsequent routine passage there is a gradual deliverance from the culture. If a massive infection is usually easier to get rid of, maybe (especially in the case of yeast) often there is resistance to antimycotic. If the culture is rare (e.g. producer of something, or the result of some experiment) - sometimes switching incubation at high sublethal doses (for each cell line is its own and is sought experimentally) from several hours to 1-2 days, followed by lowering the concentration to non-toxic.