Otherwise she will just ask for "Mucinex" because it worked really well that one time. This ignores the fact that like all of the *Quils, Sudafeds, Tylenol Cold-Flu-and-Explosive-Diarrheas, and Robitussins, there are multiple preparations made from various ingredients.
If I need an expectorant, I want guaifenesin. Cough suppressant: dextromethorphan. Decongestant: psuedoephedrine. Pain reliever: acetaminophen or ibuprofen or whatever.
It also doesn't help that it's hard to find the specific mix you need in a single preparation but it's also gotten harder to find just single ingredient store brands of some of these as well.
I don't want to take something I don't need so I'd rather not just buy some name brand kitchen-sink capsule that adds various decongestants or antihistamines if I don't need them.
But then the same focus on brand names and basic descriptions can lead to people buying homeopathic sugar pills because they're in the same department and list similar symptoms. If you never shop by ingredient, you won't know that a 1000x diluted extract of duck liver isn't the same as pseudoephedrine and guaifenesin.
It's not just patients either. Some OTC products are covered by some insurance plans. I've had prescribers change from one OTC product to another that shared none of its ingredients with the first. Not sure what they were treating other than "patient wants a prescription".
And don't get me started on homeopathic products. I had a man come in once with the box of a homeopathic product looking to buy more for his wife. I looked around, showed him a similar product, and asked if this was OK. He said it was as long as it worked as well. That I could guarantee!
I do try to dissuade such purchases, but when the customer comes in knowing what they want, it's often a losing battle. The one time homeopathic products can be useful is when someone just has to have something to treat their two-year-old's cold.
I actually did rest and drink plenty of fluids when I had a horrible cold.
I stayed in bed for most of the next 24 hours, sleeping when I could, at a comfortable room temperature and with a little ventilation.
I made sure I drank several pints of water during that time, even though at first my sore throat was hurting every time I swallowed and I really didn't want to.
One day later, a condition that had felt like it was going to give me at least another week of unpleasantness was already greatly improved. Not fully recovered, but much, much better, far beyond anything any cold remedy medication had ever done for me (though the real medicine did also help with decongestion and allowing enough comfort to fall asleep).
It turns out that doctors have been right all along and it was just me not getting it, fooling myself into thinking that if I went to bed a bit early and had a few extra sips of water then I was following the doctors' advice.
I took megadoses of vitamin C and my cold I was sure would knock me out for a week went away!
Except that taking proper rest and fluids has consistently helped me to get over anything like colds ever since, and as far as I'm aware it is the only common factor that changed other than my age.
But I have relatives that make similar statements about lots of health treatments that are absolutely not supported by the data, and probably just demonstrate variability and placebo effect.
It's dangerous to assume that just because the "cold medicine" doesn't attack the virus that it doesn't work.
This isn't strictly true either. An otherwise healthy person's body will take care of most sinus infections[1] itself given a little time and care. When it turns into something longer-term, that's when antibiotics may come into play.
[1] And these can be bacterial or viral
Did once - burst an eardrum and had to take a while off work.