Flu symptoms and online flu treatment in Puerto Rico

The flu is an infection of the nose, throat and lungs caused by influenza viruses. Unlike a cold, which comes on gradually, flu usually starts abruptly. If it is a milder cold with a runny nose and sneezing (what many Puerto Ricans call a *monga*), read common cold.

Fever usually lasts 3 to 4 days; other symptoms improve in 7 to 14 days, and the cough and tiredness can linger for weeks. Antibiotics don’t work on flu, because it is caused by a virus. The most important complication is pneumonia.

Request a visit online 24/7 — we confirm your time by email or text.

The flu is handled in a US$79 doctor visit, the same price for every age, with no membership. You pay by card when you request the visit, and you get a full refund if the visit can’t take place. A doctor’s note after your visit is included at no extra charge.

We do not bill insurance; the lab and the pharmacy charge separately. See all prices. The service is run by The Health Initiative, a nonprofit.

The most common symptoms are:

• Fever or feeling feverish, with chills
• Cough
• Sore throat
• Stuffy or runny nose
• Muscle or body aches
• Headache
• Extreme tiredness
• Vomiting and diarrhea, more common in children

Flu antivirals are prescription medicines. They work best when started within two days of the first symptoms, can shorten the illness by about a day, and may reduce some complications. The CDC recommends early treatment for people at higher risk; most healthy people with mild symptoms don’t need them.

Book early if you have flu and are in a risk group: 65 and older; children under 5, especially under 2; pregnancy; asthma or other lung disease; heart disease, diabetes, or kidney or liver disease; a weakened immune system from illness or medicines; severe obesity, or neurological or blood conditions such as sickle cell disease.

Flu or COVID? The CDC says you cannot tell them apart by symptoms alone; testing is needed. COVID-19 home tests are sold over the counter at pharmacies; if yours is positive, see COVID-19. You can have both infections at once.

In Puerto Rico, flu or dengue? A fever can also be dengue: fever with aches behind the eyes or in the muscles, joints or bones, nausea, vomiting or a rash. Puerto Rico had 6,291 confirmed dengue cases in 2024, according to a CDC report. If dengue is possible, do not take aspirin or ibuprofen; the CDC recommends acetaminophen. If needed, the doctor gives you a lab order for testing. Read dengue warning signs.

Most healthy people recover at home. In the meantime:

• Rest and drink plenty of fluids.
• Use acetaminophen or ibuprofen for fever and aches as the label directs (acetaminophen if dengue is possible).
• Stay home while you are sick. The CDC says you can go back to normal activities when, for at least 24 hours, your symptoms are getting better and you have had no fever without fever-reducing medicine.
• For the next 5 days, take extra care: wash your hands, wear a mask around others and avoid close contact.
• The best protection is a flu vaccine every year for everyone 6 months and older.
• Wash your hands with soap and water for at least 20 seconds, and cover coughs and sneezes.

Children under 5, and especially under 2, are at higher risk of flu complications. The American Academy of Pediatrics (AAP) advises contacting a doctor within 24 hours of the first symptom if your child is under 5 or has asthma, diabetes, a heart condition or another chronic illness. Prescription antivirals can be a safe and effective treatment for children, with the dose based on age and weight.

The doctor evaluates your child by video with you on camera and, if appropriate, prescribes and we send the prescription to your pharmacy. Never give aspirin to a child or teen with flu, because of the risk of Reye syndrome. Ibuprofen can be used from 6 months, but not if a child is dehydrated or vomiting continuously, and over-the-counter cough and cold medicines are not recommended under age 4. Patients under 21 need a parent or legal guardian on camera with ID. See our online doctor for kids.

For safety: a baby under 3 months with a temperature of 100.4 °F (38 °C) or higher needs the emergency room right away. Also go to the ER if your child is breathing fast or with difficulty, has ribs pulling in with each breath, hasn’t urinated in 8 hours, is not alert or has a fever above 104 °F (40 °C).

For your safety, go to the emergency room or call 911 if you have these signs. See when to go to the ER.

• Difficulty breathing or shortness of breath
• Persistent pain or pressure in the chest or belly
• Persistent dizziness, confusion, or being hard to wake
• Seizures
• Bluish or gray lips or face
• Severe muscle pain or severe weakness
• Dehydration: no urine in 8 hours, dry mouth
• Symptoms that improve and then come back worse
• A baby under 3 months with a temperature of 100.4 °F (38 °C) or higher