Influenza A is treated with a combination of prescription antiviral medications and at-home symptom management. The single most important factor in treatment is timing: antivirals work best when started within 48 hours of your first symptoms. Most people recover in five to seven days, though fatigue can linger beyond that.
Why Timing Matters With Antivirals
Antiviral medications don’t kill the flu virus outright. They block its ability to replicate inside your body, which means the sooner you start them, the less virus your body has to fight. The 48-hour window from the onset of symptoms is the standard cutoff for starting treatment, though people who are hospitalized or at high risk for complications should begin antivirals as soon as possible, even beyond that window.
If you develop flu symptoms during a known outbreak, or after close contact with someone who tested positive, getting tested and requesting a prescription quickly can shave a day or more off your illness and significantly reduce the risk of serious complications.
Prescription Antiviral Options
Four FDA-approved antivirals are currently recommended for influenza A in the United States. The most commonly prescribed is oseltamivir (Tamiflu), taken as a pill twice daily for five days. For adults, the standard dose is 75 mg per dose. Children’s doses are weight-based, ranging from 30 mg to 75 mg twice daily depending on body size.
A newer option, baloxavir (Xofluza), requires just a single dose. It’s approved for people aged 5 and older who have been symptomatic for 48 hours or less. The dose depends on weight: 40 mg for those under 80 kg (about 176 pounds) and 80 mg for those above. The convenience of one dose makes it appealing, and it works through a different mechanism than oseltamivir, which can matter if resistance is a concern.
Two other antivirals exist but are used less often. Zanamivir (Relenza) is an inhaled medication taken twice daily for five days, approved for ages 7 and up. Peramivir (Rapivab) is given as a single intravenous infusion, typically in a hospital or clinic setting.
One important note: an older class of antiviral drugs called adamantanes (amantadine and rimantadine) is no longer recommended. Nearly all circulating seasonal influenza A viruses in the United States are resistant to them. If someone suggests these, they’re outdated for flu treatment.
Who Needs Antivirals Most
Antivirals are recommended for anyone with the flu, but they’re especially critical for people at higher risk of dangerous complications. The CDC prioritizes prompt antiviral treatment for:
- Adults 65 and older
- Children younger than 2
- Pregnant women, including up to two weeks after delivery
- People with chronic conditions like asthma, COPD, diabetes, heart disease, kidney or liver disorders, or sickle cell disease
- People with weakened immune systems from illness or medication
- People with a BMI of 40 or higher
- Residents of nursing homes or long-term care facilities
- People who have had a stroke or have neurological conditions
If you fall into any of these groups, don’t wait to see if your symptoms worsen. Contact your doctor or an urgent care clinic at the first sign of flu symptoms.
Managing Symptoms at Home
Whether or not you take antivirals, most of your recovery will happen at home. Over-the-counter medications can make the experience significantly more bearable, though they don’t shorten the illness itself.
For fever and body aches, acetaminophen (Tylenol) or ibuprofen (Advil, Motrin) are the go-to options. Both reduce fever and relieve the deep muscle pain that makes flu feel so different from a regular cold. One caution: children and teenagers should not take aspirin during a viral illness due to the risk of a rare but serious condition called Reye’s syndrome.
For congestion, decongestant nasal sprays can shrink swollen nasal passages and provide quick relief, but limit use to a few days to avoid rebound congestion. Expectorants help thin mucus so it’s easier to cough up, which is useful if you’re dealing with a heavy, productive cough.
Hydration and Rest
Fever, sweating, and reduced appetite can dehydrate you faster than you realize. Water is the foundation, but you can supplement with electrolyte drinks if you’re sweating heavily or struggling to eat. Herbal teas, natural juices, and clear broths all count toward your fluid intake.
If nausea or vomiting makes it hard to keep liquids down, try ice chips or popsicles. Avoid alcohol, caffeine, and energy drinks, all of which can worsen dehydration. Spicy foods, heavily processed snacks, and sugary foods are also worth skipping until you’re on the mend.
Rest sounds obvious, but it’s worth taking seriously. Your immune system does its heaviest lifting while you sleep, and pushing through flu symptoms to work or exercise typically extends your recovery. Most people feel their worst during days two through four, with symptoms lasting five to seven days total. Even after the fever breaks and the cough fades, residual fatigue is common and can hang on for days beyond that.
Emergency Warning Signs
Most flu cases resolve on their own with rest, fluids, and time. But certain symptoms signal that the infection is becoming dangerous and needs immediate medical attention.
In adults, watch for difficulty breathing or shortness of breath, persistent pain or pressure in the chest or abdomen, confusion or dizziness that won’t clear, seizures, inability to urinate, and severe weakness or unsteadiness. A fever or cough that improves and then comes back worse is also a red flag, as this pattern can indicate a secondary bacterial infection like pneumonia.
In children, the warning signs include fast or labored breathing, bluish lips or face, ribs visibly pulling in with each breath, refusal to walk due to severe muscle pain, and signs of dehydration like no urine for eight hours, dry mouth, or no tears when crying. For infants younger than 12 weeks, any fever at all warrants immediate medical evaluation. A child who is not alert or not interacting when awake also needs urgent care.