If this is a 'Hair - 811 - 5DSP/EXP OPI HAIR' drug test for an employer, they can be testing for a range of things or something specific. You're within your rights to ask exactly what they're testing for if you're worried about something.
As cotinine is a product that can form after nicotine enters the body, I'll give you some information on testing for nicotine. Cotinine is considered the best biomarker for nicotine consumption so if they're doing a nicotine test, they'll probably be looking for it.
Employers testing for cotinine & nicotine
Employers can test for nicotine, but as I said before, you're allowed to ask them what they're looking for. The only reason I can think of that they'd be looking for nicotine is if the job prohibits smoking. If that's the case the only real option is to look into a smoking cessation program. This also applies to health insurance tests!
These tests may also be carried out if your doctor suspects a nicotine overdose.
The other components of the 'Hair - 811 - 5DSP/EXP OPI HAIR' will probably be the main drugs of abuse, plus opiates including painkillers.
These are -
• Cocaine
• Marijuana
• Amphetamines
• Methampetamines
• Opiates (Codeine, Morphine and Heroin)
• Phencyclidine
• Ecstacy
You can find a list of 'extended opiates' here:
www.fda.gov/drugs/drugsafety/Informationbydrugclass/ucm25173