During this cold season, many people may find that their favorite cold medication is not packing the punch it used to.
An active ingredient in many cold medications -- the decongestant pseudoephedrine -- is no longer allowed in drugstore aisles because in large quantities it can be used to make the illegal drug methamphetamine.
"If you are in a convenience store, a grocery store, an airport, you are not going to be able to get the decongestant that is actually effective," said Dr. Leslie Hendeles of the University of Florida.
The Food and Drug Administration now requires pharmacies to keep medications with pseudoephedrine behind the counter and available only with photo ID and signature.
Many consumers using pseudoephedrine-based medicine for perfectly legal reasons find the new regulations excessive and inconvenient.
"I was aggravated because I use Sudafed all the time. I felt like I was buying an illegal substance or narcotic," said one female drugstore customer.
Some cold medicine manufacturers have changed their formula to keep their products on the shelves and now use an ingredient called phenylephrine, which many say doesn't work as well and must be taken more often.
"For some people, there have been complaints that it doesn't last quite as long, doesn't work quite as well as pseudoephedrine," said David Morgan of the American Pharmacists Association.
Other manufacturers, like the makers of Claritin-D, stuck with their original product, even if it meant being put behind pharmacy counters.
Jared Bughough, whose 1-year-old son was congested with a heavy cough, was looking for something to ease his symptoms. Now the choices are severely limited. .
"They used to make Sudafed drops, which now they don't have over the counter anymore. There is really no alternative," said one drugstore pharmacist.
Drug companies stand by the new products.
McNneil Healthcare, which makes Tylenol cold medication, said both the old and new drugs "have been found safe and effective ingredients by the FDA."
Many people, however, are still coughing their way through winter.
ABC News medical editor Dr. Tim Johnson has some tips on dealing with colds this winter.
Remember that you can still get products with pseudoephedrine. You just have to ask your pharmacist.
If your main symptom is nasal decongestion, you can try drops and sprays such as Afrin, which often work faster than oral medication. You can only use them for three days, or you can get what is called decongestive rebound.
Elevate your head while lying down.
Drink plenty of fluids.
Use a saline rinse.
Inhale steam from a hot shower, vaporizer or kettle.
There is a new product called Zicam, a popular gel-based zinc. In labs, it's been shown to suppress the cold virus. Some people use it by putting it on a cotton-tipped swab and applying it to the inside of their nose.