A Scone man faced being sacked after a routine test mistook indigestion tablets for the Class A drug crystal meth.
Steve Clark, who works offshore, was accused of taking banned substance methamphetamine after drug analysis misinterpreted a positive result for the over-the-counter medication for an unsettled stomach.
The 38-year-old underwent a second test, which was carried out by his employer a company involved in offshore drilling which also showed a positive result for the illegal drug.
The tests could have resulted in him losing his job were it not for the detective work of his wife, Carol.
Mrs Clark, a dental hygienist who runs Gentle Hygiene Tayside, found suggestions online that claimed one of the ingredients in the indigestion pill, ranitidine, could give false positives for methamphetamine.
After her husband told his employer, a third test was carried out which came back negative. Mr Clark said he had only resorted to taking the medication after his usual prescription ran out.
He said: “I usually take Lansoprazole on prescription from the doctors, but had run out.
“Normally I don’t need to take the medication too often when I am at home, because we eat quite healthily, but when I work away it’s not so easy to control what I eat as there is less choice.
“So, in preparation for the job I took a ranitidine at breakfast on the Sunday, but was starting to suffer from indigestion by the time I got to Tain. I took another before I went to bed.
“I have other medication which I take routinely every morning, alongside my Lansoprazole. So, when I got up on the Monday morning, I took a further dose of ranitidine along with my other medication.”
Mr Clark added: “I declared my medication, including the ranitidine, before the test was carried out. I have never taken methamphetamine in my life, so was naturally shocked and confused at the accusation.”
He added that had it not been for his wife’s investigation he could have lost his job and the couple could have struggled financially.
Luckily a third laboratory test was authorised, allowing Mr Clark to clear his name.
He said: “The full test from the job site came back as consistent with my declaration of medication. No methamphetamine.
“This could have been a career-stopper for me, had my client chosen not to carry out the full laboratory test and had decided that the initial site test was proof enough of my guilt.
“That would have meant no ability to pay our mortgage and bills.”