With influenza at widespread levels across the country, fears about adverse psychiatric side effects of the prescription drug Tamiflu have also gone viral on social media.

Now people are questioning if they should be worried about taking the drug. Some have also expressed doubts about whether the drug is effective at all.

Experts at University of Tennessee Medical Center verified the facts about Tamiflu. Pharmacist Brian McCullough specializes in infectious diseases and says Tamiflu is an effective treatment to slow the spread of flu.

Brian McCullough, pharmacist at UT Medical Center.
Brian McCullough, pharmacist at UT Medical Center.

"The class of medication is neuraminidase inhibitor, which is a bit of a mouthful. Tamiflu actually prevents the virus from leaving the cell once it infects it," McCullough said. "You get less virus in your body and you can also potentially transmit less virus to other people. It is not a cure for the flu, but it can shorten the duration."

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Basically, if the virus checks into your body, Tamiflu makes it more difficult for it to spread from infected cells.

The drug can treat the flu if you start taking it within the first 48 hours of symptoms. After a couple of days of flu symptoms, the virus has likely already spread in your body and Tamiflu would not be very effective, according to McCullough.

A pharmacist at UT Medical Center holds boxes of Tamiflu and the generic brands of the same drug.
A pharmacist at UT Medical Center holds boxes of Tamiflu and the generic brands of the same drug.

Tamiflu can also help healthy people avoid the flu in the first place. Healthy medical staff at the hospital who encounter large amounts of flu cases have been prescribed Tamiflu.

"If you do not have influenza, but people around you do, you can actually take a lower dose and that can actually help prevent you from developing influenza yourself. You would take it once a day instead of twice a day [for prevention]," McCullough said. "I have actually taken it myself this year."

Tamiflu is approved for nearly all ages, from infants to the elderly. Side effects are usually upset stomach or headache.

Tamiflu box angled-60988
A box of Tamiflu capsules at UT Medical Center.

McCullough says there are verified incidents of children reporting adverse mental side effects.

"Parents are very concerned about this. There have been rare reports of hallucinations and psychiatric symptoms in children. Those side effects are self-limiting, so if you stop taking the medication the symptoms will resolve. And they're very, very rare. The drug is usually well-tolerated," McCullough said.

Parents should discuss the benefits and risks of Tamiflu with their pediatrician and always monitor the side effects of any medication, according to McCullough. He also emphasized Tamiflu is only one of many tools available to fight the flu.

Tamiflu box at UT Medical Center.
Tamiflu box at UT Medical Center.

"Tamiflu is not a substitute for a flu shot. You should get a flu shot and it will still help this season. If you get the flu after you get a shot, the symptoms will probably not be as severe. You should also use good hygiene with your hands and wash them regularly," McCullough said.

UT Medical Center's pharmacy has not experienced any shortages of Tamiflu this year. Some social media posts have contributed to rumors of a mass shortage, but 12 News's sister-station in Tennessee, WBIR, spoke to dozens of pharmacies in East Tennessee and none reported a reduced supply of Tamiflu.

Another question on people's minds is can those who have already had the flu this year catch the virus again. UT Medical Center's spokesperson Susan Wyatt said it is possible because there are multiple strains of the virus. You will not be infected by the same strain of influenza twice, but could potentially catch one strain and then be infected by a different strain.