You don't need to go to medical school to be your own doctor for a cold. Over-the-counter (OTC) medicines can provide relief, but choosing the right one can cause a headache, said Dr. John Messmer, associate professor of family and community medicine at Hershey Medical Center.

"There's a whole variety of stuff that may or may not help," he said. "There's nothing magic about OTC medicines. People are usually buying into hype that promises to make you feel better."

The cold and flu cannot be treated with antibiotics because they are caused by viruses, said Dr. Bruce Jansen, clinical director of the general medicine department of university health services. A cold is caused by the Rhinovirus and usually has the symptoms of sneezing, sore throat, cough and headache. The flu is caused by the influenza virus and tends to hit more quickly and more severely than a cold with higher fever, aches and fatigue, sore throat and hacking cough, he said.

The flu is preventable through a flu vaccination. Also, a medicine for the flu has been developed which if taken just as symptoms appear lessens their duration and severity, Jansen said.

"It cuts down the length of sickness by about one day if taken in the first 48 hours," he said. "After that it doesn't help."

Doctors can't prescribe medicine to eliminate the cold virus and the flu virus after the first two days, but people can still find ways to feel better through OTC medicines. "OTC medicines only provide symptom relief," Messmer said. "They don't cure anything.

"There are only a limited number of OTC medications that can treat the cold," he added. "If you look at the packages they are just variations of different drugs."

Some OTC medicines for colds feature multi-symptom relief for fever, cough and congestion, but these may not be the best thing to take, Messmer said. You may get a medicine that's unnecessary or take too much of a medicine.

If you take an OTC medication and you don't have the symptom, nothing could happen or there could be an effect but with little or no benefit. Taking too much could have dangerous side effects.

"With multisymptom medications you may take something that you don't need," Messmer said. "Taking a specific medicine for a specific symptom is best."

For congestion, look for OTC products with pseudoephedrine, the only oral OTC decongestant. It is also known as Sudafed. If taken without having the symptoms, Sudafed may dry out your nose, but if too much is taken, it could lead to high blood pressure, Messmer said.

Antihistamines such as diphenhydramine, triprolidine, chlorpheniramine and brompheniramine are commonly used in OTC medicines to dry out membranes and help a person to sleep.

For coughing, there is only one OTC medicine called dextromethorphan, which reduces coughing in some people. It can interact with some antidepressants and one in seven people do not metabolize it properly and can experience hallucinations. It also sedates if too much is taken.

For fever reduction and aches and pains, acetaminophen (Tylenol) can help, but if taken in more than the recommended amount or with alcohol, it can lead to liver damage. Ibuprofen (Advil or Motrin) and asprin have the added advantage of reducing inflammation, however, too much ibuprofen and asprin can lead to stomach irritation and ulcers.

There has been some speculation that zinc, vitamin C and echinacea help to shorten the duration of the flu, but the result are not conclusive, Jansen said.

"When I'm sick, I eat healthier and get vitamin C from orange juice," said Alvin Tan (senior-computer science, mathematics). "I heard it helps the immune system and maybe if I believe it works, it will."

Regardless of their effectiveness, taking these supplements won't hurt, Messmer said. He also agrees that belief plays a role.

"A lot of relief comes from the expectation of relief," he said.

To get the maximum amount of relief from OTC medications, people should always look at the package directions for the correct dosage and frequency that they should take them, Jansen said.