Preparing For The Cold and Flu Season

Get ready for cold and flu season with our expert guide that covers the causes, symptoms, and ways to boost your immunity.

Updated: Wednesday 12 November 2025


Flu Season

The NHS started its annual flu vaccination campaign at the beginning of September this year. This coincides with the weather getting colder as well as children returning to schools, where there’s a significant risk of contracting seasonal infectious diseases.[1]

But flu season has arrived more than a month earlier than usual in 2025, with cases of flu three times higher than this time last year.[2] To prepare for this early wave of flu, the NHS is urging everyone eligible to get vaccinated as soon as possible.

Vaccinations are a vital defence, but there are several additional measures our pharmacists recommend to prepare for cold and flu season.

Keep reading to learn about the symptoms of cold and flu and the most important steps you can take to prepare yourself this autumn and winter.

When is the cold and flu season?

The cold and flu season can occur anytime from the beginning of autumn to spring. It tends to peak between December and March when seasonal flu transmissions are highest. This is due to factors such as exceptionally cold weather affecting our immune systems in the winter.[3]

Cold vs flu

Causes

The latest research states that colds can be caused by over 200 types of viruses.[4] Many of these viruses are classified as ‘rhinoviruses’ because they primarily infect the nose (‘rhin’ is the Greek word for the nose).[5] In contrast, the flu can only be caused by one type of virus known as influenza.

Rhinoviruses and influenza viruses affect the body via the same mechanism. They enter the body through the respiratory tract before injecting their genetic material into cells to infect them. This causes the viral genome to be replicated, resulting in new virus particles that can infect other cells.[6]

Symptoms

Cold and flu symptoms are similar but not identical. The table below summarises the main cold and flu symptoms and their likelihood of occurring.

Symptoms Likelihood of the symptom occurring with a cold Likelihood of the symptom occurring with the flu
Stuffy nose High Occasional
Sore throat High Occasional
Headache Occasional High
Fever Low High
Aches Occasional High
Chills Low High
Fatigue (Body weakness) Occasional High
Sneezing High Occasional
Coughing and chest discomfort High (but often mild) High (potentially severe)

Flu symptoms are typically more severe than cold symptoms and begin more abruptly. In many cases, the flu is accompanied by a fever, which can cause chills, headaches, and a raised temperature.

Our pharmacists recommend keeping a digital thermometer handy to accurately measure body temperature. This can help indicate whether someone has contracted the cold or flu.

While the common cold does not typically pose any major health risks, it’s important to know that the flu can cause serious complications. These include sinus and ear infections, as well as pneumonia in severe cases.

You should see your GP or a medical professional as soon as possible if you experience:

  • difficulty breathing
  • persistent chest and/or abdominal pain
  • severe muscle pain
  • persistent dizziness

These symptoms can indicate a more severe condition which needs immediate medical attention.

Virality

The influenza virus that causes the flu consists of 8 RNA segments compared to the single RNA strand within viruses that cause colds, such as rhinoviruses.

This means influenza can mutate (change the structure of its genes) faster than rhinoviruses because it has multiple RNA segments that can be rearranged to create new strains of the virus.

Seasonality

‘Common cold’ and ‘seasonal flu’ are often used to describe cold and flu because of the belief that colds can occur year-round, while flu only occurs during the colder seasons.

This is not fully true, as both colds and flu can be caught year-round. But there is evidence that suggests flu is more likely to occur seasonally, during the colder months.

The influenza virus is more stable when it’s colder and drier, meaning it can survive and remain infectious more easily. Studies found that the virus transmission was most efficient at 5°C, but was inefficient or blocked at 30°C.[7] Another study found that animals that were kept at 5°C shed (released) higher concentrations of influenza after infection than those kept at 20°C.[8]

Colder weather also makes people more likely to stay indoors with the heating on. Heating reduces humidity, making it easier for influenza to survive and spread, as dry air is the ideal environment for the virus. Spending more time in enclosed spaces with limited ventilation increases the chances of contracting the flu significantly.

See our ultimate guide to cold and flu to find answers to common questions about cold and flu.

Key steps to prepare for the cold and flu season

Step 1: Get vaccinated

Vaccination is one of the most important defences against cold and flu. Research shows that flu vaccines can reduce the risk of hospitalisation from severe flu symptoms by 40% in adults and by up to 75% in children.[9][10]

Flu vaccines are typically available through private providers. The NHS has also made flu vaccinations available at no cost to individuals who belong to one or more of ten categories of people deemed to be at an increased risk from flu.

Step 2: Stock treatments for cold and flu

Decongestants

Decongestants, such as phenylephrine (an ingredient in Lemsip Max capsules and Lemsip Max sachets), can reduce inflammation and swelling in the nasal passages by narrowing blood vessels in the nose.[11] This helps relieve symptoms such as a blocked or stuffy nose.

Some decongestants are not suitable if you have a heart condition, such as high blood pressure. Vicks VapoRub or Olbas Oil are effective alternatives for people who cannot use these treatments.

Cough syrups

Coughing is a natural reflex that helps clear mucus from the airways. While coughing is a symptom of both cold and flu, severe coughing episodes and chest discomfort or pain are more likely to occur with flu.

Chesty cough syrups are recommended if you have a build-up of mucus, as they can loosen phlegm and make it easier to cough up. On the other hand, if you get recurring bouts of coughing, dry and tickly cough syrups can help suppress the cough reflex. It works by stopping the brain from sending signals that trigger coughing.

We recommend contacting our pharmacy team or your GP before taking any type of cough syrup.

Antiviral treatments

Antiviral treatments can shorten the duration of the flu by preventing the influenza virus from replicating in the body. Some antiviral treatments, such as Tamiflu, are available to individuals who pass a medical assessment and can be especially effective when used alongside personal protective equipment (PPE) such as face masks for flu prevention.

Antivirals should not be used to treat the common cold, as they will not be effective. The common cold is caused by hundreds of rapidly mutating viruses (mainly rhinoviruses), so they cannot be targeted effectively by a single treatment.

Pain relief treatments

Pain relief treatments can be effective at reducing head and body aches associated with colds and flu.

The table below summarises three effective pain relief treatments for cold and flu, as well as their mechanisms and the symptoms they can help relieve. Consult our pharmacy team or your GP before taking any of the treatments below.

Active Ingredient/Treatment Mechanism Primary symptom(s) relieved
Paracetamol (available on its own or as part of Lemsip Max capsules/sachets) The exact mechanism of action for paracetamol is still being researched.

Some studies suggest that paracetamol may inhibit COX enzymes that convert arachidonic acid to prostaglandin (a chemical that plays an important role in inflammation and pain).[12] However, paracetamol does not have anti-inflammatory effects.

There is also research to suggest that paracetamol can affect several pain pathways in the brain.[13]
Headache, body ache, fatigue, chills
Ibuprofen (available on its own) Ibuprofen inhibits COX enzymes so they stop producing inflammatory prostaglandins.

This is why ibuprofen is classified as an NSAID (non-steroidal anti-inflammatory drug).
Headache, body ache, fatigue, chills
Phenylephrine (part of Lemsip Max capsules/sachets) Phenylephrine reduces nasal swelling by narrowing blood vessels in the nose.[14] Stuffy nose, sore throat

Step 3: Boost immunity through nutritional supplements

Certain vitamins can help you prepare for the cold and flu season by bolstering the body’s natural immunity and reducing inflammation.

Our pharmacists recommend these three vitamins to help protect against cold and flu symptoms, as their effectiveness is backed by scientific research.[16][17]

  1. Vitamin D (from sun exposure) increases the production of antimicrobial peptides that can kill viruses that cause the cold and flu.
  2. Zinc (from certain foods such as meat, chickpeas, or almonds) can help reduce inflammation by inhibiting the production of pro-inflammatory cytokines in the body.
  3. Vitamin C (from citrus fruits) can increase the production of white blood cells and antibodies to fight off cold and flu viruses.

Step 4: Follow a sleep schedule

According to multiple studies, getting sufficient sleep every day can increase the body’s production of T cells (a type of white blood cell) and counter pro-inflammatory signalling in the body.[18][19] Both these mechanisms can help reduce the probability of being infected with cold and flu viruses.

It’s also important to consider sleep timings. Going to bed and waking up at the same time every day can help regulate physical, mental, and behavioural changes following a 24-hour day and night cycle, known as the circadian rhythm. This can subsequently help with regulating the secretion of proinflammatory cytokines that affect the immune system.[20]

Therefore, following a sleep schedule that allows for 6 to 8 hours of high-quality sleep every night can help prepare the body for the cold and flu season ahead.

Read our complete guide to sleeping better at night for tips on getting the best quality sleep.

Preparing for a super cold

What is a super cold?

The term ‘super cold’ first gained traction after the peak of COVID-19 in 2021. At the time, an article by the BBC described the super cold as "the worst cold ever" because of its severe symptoms, such as excessive fatigue, a heavy and frequent cough, and a constantly runny nose.[21]

Symptoms of a super cold

The symptoms of a super cold are identical to those of a cold, even though they can be more severe. Therefore, it's recommended to prepare for a super cold in the same way you would prepare for the cold and flu season.

Treatments for super colds

The symptoms of a super cold can be relieved using the same treatments that are typically recommended for those with a common cold. Consult our pharmacy team or your GP about suitable treatments and dosage strengths.

Stock treatments now to prepare for the cold and flu season

Our team of experts at Pharmica help countless people prepare for the cold and flu season each year. We offer MHRA-approved cold and flu treatments that can help relieve symptoms effectively, and we deliver to home and work addresses for maximum convenience.

We also provide health and lifestyle advice based on the latest research through our Health Hub on an array of additional conditions, including weight loss, erectile dysfunction, and more.

With a 4.9 out of 5 rating from over 230,000 reviews and over a 1.8 million patients served, we’re proudly transforming the digital pharmacy experience in the UK.

Browse our full range of treatments today.

  1. Donaldson et al. 2020. Risk factors associated with outbreaks of seasonal infectious disease in school settings, England, UK.
  2. National Health Service. 2025. Early flu wave could lead to ‘long and drawn out’ Winter for NHS.
  3. Bupa. 2023. Can cold weather really make you ill?
  4. Harvard Health Publishing. 2023. Common cold (viral rhinitis).
  5. Centers for Disease Control and Prevention. n.d. Rhinoviruses.
  6. Zhu et al. 2022. A structural understanding of influenza virus genome replication.
  7. Lowen et al. 2014. Roles of Humidity and Temperature in Shaping Influenza Seasonality.
  8. Lowen et al. 2007. Influenza Virus Transmission Is Dependent on Relative Humidity and Temperature.
  9. McLean et al. 2023. Interim estimates of 2022–23 seasonal influenza vaccine effectiveness — Wisconsin, October 2022–February 2023.
  10. Olson et al. 2022. Vaccine effectiveness against life-threatening influenza illness in us children.
  11. Stanford Medicine. n.d. Eustachian tube dysfunction.
  12. Ayoub 2021. Paracetamol (acetaminophen): A familiar drug with an unexplained mechanism of action.
  13. Sharma & Mehta. 2013. Paracetamol: mechanisms and updates.
  14. Medline Plus. n.d. Phenylephrine.
  15. NHS. n.d. Antihistamines.
  16. Moore and Khanna. 2022. The role of vitamin C in human immunity and its treatment potential against COVID-19: A review article.
  17. Zhu et al. 2022. Association between vitamin D and influenza: meta-analysis and systematic review of randomized controlled trials.
  18. UC Health. 2020. Creating better sleep habits to strengthen immunity.
  19. Garbarino et al. 2021. Role of sleep deprivation in immune-related disease risk and outcomes.
  20. Haspel et al. 2020. Perfect timing: circadian rhythms, sleep, and immunity — an NIH workshop summary.
  21. BBC. 2021. Super cold: Is 'the worst cold ever' going around?
Kamran Bell

Written by: Kamran Bell

Pharmacist・GPHC Number 2231070

Kamran graduated with a four-year master's degree in pharmacy from Aston University in 2021. He completed a pre-registration year at a community pharmacy before working there for a further year. At Pharmica, Kamran provides expert patient advice and addresses clinical questions to ensure the health and well-being of our patients.


Ana Carolina Goncalves

Medically Reviewed by: Ana Carolina Goncalves

Superintendent Pharmacist・GPHC Number 2088658

Ana Carolina Goncalves is the Superintendent Pharmacist at Pharmica, where she ensures patients receive exceptional healthcare and support, as part of a seamless online pharmacy service.

With a comprehensive professional background spanning more than 13 years, Ana Carolina has extensive experience supporting Men’s and Women’s health. Ana Carolina is responsible for providing expert treatment advice to thousands of patients in areas such as Sexual Health, Erectile Dysfunction, Hair Loss, Weight Loss and Asthma.


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How to Boost Your Immune System in Winter
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