A mosquito bite that won't stop itching: how can you relieve it?

Mosquitoes are small flying insects belonging to the Culicidae family, which comprises several thousand species worldwide. Among mosquitoes, only the females bite, as they need the proteins found in blood to ensure the development of their eggs. When a mosquito bites us, it inserts its slender proboscis through the skin into a blood vessel, injects saliva rich in anticoagulants and mild anaesthetics, and then draws blood.

It is this saliva, which our immune system recognises as foreign, that triggers a defence reaction. The body then releases histamine, a molecule involved in inflammation, which is responsible for the redness, swelling and, above all, the itching.

Mosquitoes are attracted by body heat, the carbon dioxide we exhale, and also by certain odours unique to each individual. After biting, they leave a small mark on the skin which, for some people, can become particularly bothersome or even persistent. The severity of the reaction varies depending on our individual sensitivity, but also on the species of mosquito involved.

The reason we sometimes experience prolonged itching after a mosquito bite is mainly due to our immune system’s reaction. When the mosquito’s saliva enters the skin, our body recognises it as a foreign substance. It then releases histamine, a chemical mediator involved in allergic reactions. Histamine causes blood vessels to dilate, leading to redness, swelling and, above all, that intense itching sensation.

Two types of immune response may explain the intensity and duration of the symptoms:

• The immediate reaction (type I)

This occurs within minutes of the bite. It is linked to the release of histamine by certain immune cells (mast cells), which causes redness, swelling, localised warmth and intense itching. This reaction is usually temporary, but can be very uncomfortable.

• The delayed reaction (type IV)

This appears several hours to a few days after the sting and involves a more profound activation of the immune system (T cells). It manifests as a persistent papule, prolonged itching and, in some cases, long-lasting inflammation, particularly in children and people with atopic or allergic skin.

Other factors can prolong the discomfort

When the itching persists for several days, this can be due to various factors:

Increased individual sensitivity: Some people react more strongly to mosquito saliva, releasing more histamine or triggering a delayed reaction, which prolongs the symptoms.

Excessive scratching: The more we scratch, the more the skin becomes irritated. This perpetuates the inflammation, can damage the skin barrier and slow down healing.

The type of mosquito: Certain species, such as the tiger mosquito, inject more irritating substances or in greater quantities, causing more severe reactions.

A secondary infection: If the bite is broken or is scratched vigorously, bacteria can enter the skin, leading to persistent redness, pain or oozing.

An allergic predisposition or an exaggerated immune response: Children and people with allergies may experience reactions that last longer, are more widespread, or even result in persistent papules. In rare cases, this is referred to as "Skeeter syndrome”, an intense local allergic reaction causing marked swelling, warmth, persistent itching and, occasionally, a mild fever.

The location of the bite: Areas where the skin is thinner or has a higher density of nerve endings (wrists, ankles, face) are often more sensitive and react more strongly.

It is therefore important to quickly soothe stings that are very itchy in order to limit irritation and prevent complications.

Here are the main signs to help you identify a mosquito bite:

• A red bump: the rapid appearance of a small red papule, often slightly raised.

• Itching: a sensation of pruritus (itching) of varying intensity, which may last from a few hours to several days. Itching may be immediate or delayed.

• A white or pinkish appearance: in some people, the bite takes on a pale appearance in the centre, surrounded by a red halo.

• Localised swelling: mild swelling around the bite, particularly common in children or people with sensitive skin.

• Localised warmth: the bitten area may feel slightly warmer than the rest of the body.

• Moderate pain: rarely present, unless the bite is in a sensitive area or has been scratched.

• Blisters: in some cases, particularly in children, small blisters filled with clear fluid may appear.

• A scab: this may form if the bite is scratched vigorously and the skin is broken.

• Varying duration: the reaction may disappear within a few hours or persist for several days, depending on individual sensitivity and the species of mosquito.

The severity and appearance of these symptoms vary depending on our immune system, our skin, the environment and the type of mosquito involved.

There are many natural remedies to soothe the itching and promote the healing of mosquito bites, including those that keep itching for a long time: 

Our natural remedies to keep at home

Soothing Bite Roll-on

A ready-to-use treatment, designed to quickly relieve itching and irritation caused by insect bites (mosquitoes, wasps, horseflies, etc.) or plants such as stinging nettles. Its synergistic formula combines essential oils of true lavender, Roman and German chamomile, a soothing calendula extract and organic menthol crystals, for an instant cooling effect and localised soothing action. Its glass roll-on applicator allows for precise and easy application. It is suitable for the whole family (adults and children aged 3 and over) and fits easily into a pocket or first-aid kit. Please note: not suitable for pregnant women or children under 3 years of age.

Discover the Soothing Insect Bite Roll-on

Aloe vera gel

Aloe vera gel has soothing, moisturising and restorative properties. When applied topically to a bite, it quickly relieves itching, reduces redness and promotes skin regeneration. Its immediate cooling effect provides long-lasting relief, particularly for sensitive or irritated skin. Apply a small amount of pure gel directly to the bite, 2 to 3 times a day until the symptoms disappear.

Discover Aloe vera gel

Green clay as a poultice

Thanks to its decongestant and absorbent properties, green clay is ideal for soothing an inflamed bite. Applied topically, it relieves discomfort, reduces swelling and helps to dry out the bite if there is a small blister or oozing.

Mix the clay with a little water to form a smooth paste, then apply a thick layer to the sting. Leave on for 10 to 15 minutes without letting it dry out completely, then rinse off with lukewarm water.

Discover green clay as a poultice

Fine Lavender Hydrosol

Refreshing and soothing, this hydrosol is ideal. Fine lavender hydrosol is a gentle, refreshing and soothing floral water. When misted onto the skin, it soothes itching, reduces redness and promotes the healing of bites. Spray directly onto the bite several times a day, or soak a compress in the hydrosol and gently dab it onto the irritated area.

Discover Fine Lavender Hydrosol

Our time-honoured home remedies that are always useful

Cold: An ice cube wrapped in a cloth and applied to the bite for a few minutes provides local anaesthesia, slows the release of histamine and reduces the urge to scratch.

Bicarbonate of soda: Mixed with a little water to form a paste, it can be applied to the bite to soothe the itching.

A cold black tea bag: Rich in tannins, it soothes irritated skin and helps reduce inflammation.

Apple cider vinegar: A few drops on a cotton pad relieve the itching thanks to its astringent and slightly acidifying effect.

A fresh plantain leaf: when crumpled and applied to the bite, it soothes inflammation and supports skin regeneration.

Honey: applied in a thin layer, it helps the wound to heal whilst soothing the itching thanks to its soothing and antibacterial properties.

All these remedies can be used as soon as the itching begins. It is best to act quickly to prevent the bite from becoming more severe. However, it is important to test on a small area the first time you use any of them, to ensure that no reaction occurs.

To avoid bites, there’s nothing better than prevention! Here are our 10 simple and effective tips to minimise the risk, particularly during the summer months or in areas with high mosquito populations:

1. Wear light-coloured, covering clothing: Opt for long sleeves, trousers and light-coloured, lightweight fabrics, especially in the evening. Mosquitoes are particularly attracted to dark colours and exposed skin.

2. Fit mosquito nets: Place them on windows, around the bed or cot, especially for babies and young children. They provide effective physical protection without the need for chemicals.

3. Avoid strong perfumes: Mosquitoes are attracted to floral, fruity or sweet smells. Opt for fragrance-free products, particularly in the evening.

4. Get rid of standing water: Regularly empty saucers, vases, buckets, watering cans and any other containers that might hold water. These damp areas are ideal breeding grounds for mosquitoes.

5. Air and ventilate rooms: Mosquitoes thrive in warm, humid and confined environments. Let fresh air in every day, especially in the morning and at the end of the day.

6. Avoid going out at dusk: Mosquitoes are most active at dusk and dawn. If possible, limit outdoor activities to these times.

7. Place mosquito-repelling plants near openings: Lemongrass, basil, peppermint or Rose geranium are known to naturally repel mosquitoes. Place them on window sills or balconies.

8. Diffuse natural repellents in your surroundings: Using air fresheners (in the form of sprays, diffusers, coils or natural candles) can help create a protective scent barrier. You can make them yourself using traditional home remedies.

9. Use suitable skin repellents: When applied directly to the skin, certain natural or certified products can effectively repel mosquitoes. Choose gentle repellents, free from controversial substances, and suitable for your child’s age and geographical area. Discover our article on the best natural repellents.

10. Stay vigilant whilst travelling: In tropical or high-risk areas, find out about the mosquitoes present (e.g. tiger mosquitoes, disease vectors) and adapt your protective measures accordingly.

Even natural remedies can cause skin reactions, particularly on sensitive skin or in young children. To ensure safe use, we recommend:

• Always carry out a skin test: apply the product to a small area (the crook of the elbow or wrist) before using it more widely.

• Never use undiluted essential oils on the skin, particularly on children, pregnant women or breastfeeding women, without consulting a healthcare professional.

• Avoid scratching the bites to minimise the risk of secondary infection or lasting marks.

• Consult a healthcare professional in the event of multiple stings, severely inflamed stings, or if there are signs of a severe allergic reaction (marked swelling, breathing difficulties, feeling unwell).

If in doubt, or if the bite becomes painful, starts to ooze pus, or does not heal after several days, it is best to seek medical advice.

Although it may be tempting, avoid scratching. This is the best way to minimise irritation and promote healing. By applying a cold compress or a soothing treatment as soon as the itching starts, you’ll help your skin to calm down… and you’ll find it easier to resist the urge to scratch.

Stéphanie Catrysse is a naturopath (certified by the FENA), a wellness massage and lymphatic drainage practitioner, and a personal development coach. Passionate about alternative medicine, she practices with a holistic approach to health.