Although metronidazole has been recommended as a treatment for symptomatic Blastocystis patients, researchers have questioned the efficacy and evidence for the benefit of this treatment. In a paper describing a case report of two Blastocystis patients, physicians report that “two Blastocystis sp.-infected individuals, who presented increased parasite load and exacerbated symptoms upon treatment with the usual recommended dosage and regime of metronidazole. The two studies uniquely demonstrate for the first time a cyst count as high as fivefold more than the original cyst count before treatment and show an exacerbation of GI symptoms despite treatment. The study provides additional support in recognizing metronidazole resistance in Blastocystis sp. and its consequences towards the pathogenicity of the parasite.” The account was published in Parasitology Research.