Treating the flu in someone 65 or older requires acting quickly, because age alone puts them in a high-risk category for serious complications. The most important step is starting a prescription antiviral medication as soon as possible, ideally within 48 hours of the first symptoms. Beyond antivirals, the right supportive care at home, careful use of over-the-counter products, and close monitoring for warning signs can make a significant difference in how safely an older adult recovers.
Start Antiviral Treatment Early
The CDC recommends prompt antiviral treatment for anyone 65 and older who has the flu or is suspected of having it. The standard prescription antiviral is taken twice daily for five days. In clinical studies, starting it early shortened symptom duration by about a day compared to no treatment, but the real benefit for older adults is reducing the risk of dangerous complications like pneumonia and hospitalization.
A newer single-dose antiviral option exists that works differently and may clear the virus faster, though its safety and effectiveness in adults over 65 still needs more clinical confirmation. For most older patients, the established five-day course remains the go-to. If the person has reduced kidney function, which is common in older adults, the prescribing doctor will likely adjust the dose. For those with moderately impaired kidney function, the typical adjustment is cutting from twice daily to once daily.
The key takeaway: don’t wait to see if symptoms improve on their own. Call a doctor at the first signs of flu (fever, body aches, cough, fatigue) and ask about antiviral treatment the same day.
Hydration Requires Extra Attention
Older adults are already more vulnerable to dehydration under normal conditions. Fever, sweating, and reduced appetite during the flu accelerate fluid loss significantly. A practical guideline is to aim for roughly 11 cups of total daily water intake for women and 15 cups for men (including water from food and beverages). During fever, an additional 500 mL of fluid is recommended for every degree Celsius the body temperature rises above 38°C (100.4°F).
For someone who struggles to drink enough fluids, water-rich foods can help. Watermelon, cucumbers, celery, lettuce, zucchini, spinach, and strawberries all contain more than 90% water. Small, frequent sips of water, broth, or an oral rehydration solution with some sodium tend to work better than trying to drink large amounts at once. Sodium helps the small intestine absorb water and helps the body retain it, so lightly salted broth is a good choice. Avoid heavily processed or very salty foods, though, as these can worsen the fluid imbalance.
Dehydration in older adults doesn’t just cause discomfort. It can trigger muscle weakness, confusion, and accelerate the loss of muscle mass, all of which make recovery harder and increase the risk of falls.
Be Cautious With Over-the-Counter Medications
Many combination cold and flu products contain ingredients that are risky for older adults, especially those with heart disease or high blood pressure. Oral decongestants like pseudoephedrine and phenylephrine raise blood pressure and can cause heart rhythm problems. People taking certain antidepressants face even greater risk when combining them with decongestants.
Multi-symptom products like DayQuil bundle a pain reliever, cough suppressant, and decongestant into a single dose. This makes it easy to accidentally double up on acetaminophen if the person is also taking another pain reliever, or to unknowingly take a decongestant that interacts with their existing medications. A safer approach is to treat individual symptoms with single-ingredient products and check each one against current prescriptions. If you’re unsure, a pharmacist can review the person’s medication list and recommend what’s safe.
Why the Flu Hits Harder After 65
The immune system weakens with age, which means the body mounts a slower and less effective response to the influenza virus. But the bigger danger is what the flu does to pre-existing conditions. Among adults hospitalized with flu in recent seasons, about half had heart disease. A 2018 study found the risk of heart attack was six times higher within a week of a confirmed flu infection, and this effect was most pronounced in older adults. Sudden, serious heart complications occurred in roughly 1 out of every 8 hospitalized flu patients.
People with heart failure should be especially alert to changes in breathing during a flu illness. Those with diabetes may see blood sugar become harder to control. Chronic lung conditions like COPD or asthma can flare severely. The flu itself may be manageable, but its ability to destabilize these underlying conditions is what drives hospitalizations and deaths in this age group.
Complication Rates Are High
The 2024-25 flu season produced the highest cumulative hospitalization rate since tracking began in the 2010-11 season. Adults 75 and older were hit hardest, with a hospitalization rate of nearly 599 per 100,000 people, more than 15 times the rate in children and teens. Among hospitalized patients of all ages, 30% developed pneumonia, about 19% developed sepsis, and 18% experienced acute kidney failure. For those 75 and older specifically, pneumonia rates reached nearly 32%.
About 17% of hospitalized flu patients required intensive care, 6% needed mechanical ventilation, and 3% died in the hospital. These numbers underscore why early antiviral treatment and attentive home care aren’t optional for older adults. They’re the difference between recovering at home and ending up in the hospital.
What Recovery Looks Like
Most healthy younger adults bounce back from the flu in one to two weeks. For older adults, recovery is slower and less predictable. Fatigue, weakness, and reduced appetite can linger for several weeks, and the period of recovery carries its own risks. Prolonged bed rest leads to muscle loss, reduced balance, and deconditioning that can outlast the infection itself.
Gentle movement, even just sitting up in a chair or walking short distances within the home, helps preserve strength. Adequate protein intake supports muscle maintenance during and after illness. Small, frequent meals tend to be more realistic than full-sized ones when appetite is low.
Warning Signs That Need Immediate Attention
Some symptoms during the flu signal that something more dangerous is happening. Contact a healthcare provider right away or go to the emergency room if the person experiences:
- Shortness of breath or difficulty breathing
- Weakness, dizziness, or confusion
- Persistent pain or pressure in the chest or abdomen
- A fever or cough that improves and then returns, which can indicate a secondary bacterial infection like pneumonia
- Worsening of any chronic condition, such as heart disease or asthma
Confusion is particularly important to watch for in older adults, because it can be the first visible sign of serious dehydration, low oxygen levels, or sepsis. Any noticeable change in mental sharpness or alertness during a flu illness warrants a call to the doctor, even if other symptoms seem stable.