Hay Fever is also medically termed as rhinitis. It can be divided into Allergic Rhinitis and Non-Allergic Rhinitis.

Allergic Rhinitis occurs when the immune system wrongly identifies a harmless substance as an allergen and responded exaggeratingly by releasing histamines and other chemical mediators causing symptoms in the nose, the roof of mouth, throat, eyes, ears and skin.

Allergic Rhinitis can occur together with allergic conjunctivitis. It can exacerbate lung disease such as asthma in people who suffers from both conditions.

Non-Allergic Rhinitis, as the name suggested, is a condition that does not involve the immune system. People with Non-Allergic Rhinitis has similar symptoms of runny nose and nasal congestion, without a trigger. This tends to occur in the adult.


Indoor allergens cause perennial allergic rhinitis, meaning the symptoms can occur all year round. Common allergens include:

Outdoor allergens cause seasonal allergic rhinitis as it occurs the different time of the year when the pollen level is high in the air. Typically, in countries with four seasons, the symptoms tend to flare during spring and fall.

Irritants such as smoke, open burning, strong odours, change of humidity and temperature of the air can trigger allergic rhinitis by causing inflammation of the nose linings, hence sensitizing the nose to irritants.


Typical symptoms include:


Your doctor will take a thorough medical history and allergy history, physically examine you. Your doctor will enquire on your lifestyle, home and work environment. An allergy diary may be useful. You may be offered allergy testing such as skin prick tests and allergy RAST blood tests to determine the triggers of your allergic rhinitis. Sometimes, your doctor may even refer you to an allergist or immunologist.


By identifying the culprit allergens, your doctor will work with you to develop a strategy to avoid the allergens as much as you can. In triggers that are inevitable such as in the case of seasonal allergic rhinitis, you may be recommended to start medications before you have contact with the allergens to prevent developing allergic rhinitis or reduce the severity of the symptoms.

Medical treatment options for hay fever include:

Consult your doctor if you have a sensitive snuffly nose! Take care.

The same medication may not cause any reaction to a person, yet may cause unforeseen allergic reactions to another person. An allergic reaction occurs when the body’s immune system mistaken a harmless substance as an allergen, in the case of a medication, triggering a cascade of allergic events.

What are the Common Medications that can produce Allergic Reactions?

What are the Symptoms of Drug Allergy?

Drug Allergy manifestations differ individually, with a wide spectrum of symptoms such as

In severe end spectrum of drug allergy, one can potentially develop anaphylaxis that if not being reversed and treated on time, can lead to death. You should seek immediate medical attention if you suspect of having anaphylaxis.

A drug history and a history of relevant symptoms are important. It would be useful to obtain the timeline relation between the start of the culprit of medication and the onset of the symptoms. Often, you may be taking multiple drugs concurrently. Your doctor will work with you to produce a drug chart to see the correlation between the drug and allergy symptoms. 

You may develop various different adverse reactions to medications that can range from stomach upset from aspirin to diarrhoea caused by antibiotics. Some people who are taking certain blood pressure medication such as ACE-I (Angiotensin-Converting Enzyme Inhibitors), can develop cough, facial and tongue swelling.

What do I expect when I consult my doctor for Drug Allergy?

Allergy testing such as skin prick tests, blood tests, or even an oral challenge test may be offered to certain suitable patients. Your doctor may work together with immunologist or allergist to further evaluate your Drug Allergy.

What are the Treatment and Management of Drug Allergies?

When drug allergic reactions occur, the offending drug should be stopped. Your doctor is likely to prescribe you antihistamine, corticosteroid or even epinephrine during serious allergic reactions.

In circumstances where there is no other alternative medication available, and the allergic medication is essential, you may be offered a desensitization procedure. Your doctor will gradually introduce the medication in small doses and monitor closely for any adverse reaction to achieve the maximum possible dose that you can tolerate and simultaneously aiming to achieve a therapeutic dose.

You may have come across the below, if not, it may be worth spending a minute of time reading.

Adverse Drug Reactions (ADRs)

ADRs: Drug Rash with Eosinophilia and Systemic Symptoms (DRESS Syndrome)

DRESS syndrome, as the name suggests, is a serious Drug Allergy that causes skin rash and involves other body systems. One can present with fever, facial swelling, rash, kidney or liver injury and swollen lymph nodes. Patients with DRESS have abnormal blood cells counts with elevated levels of eosinophils. Eosinophils are blood cells that are associated with allergic conditions.

Almost any drug can cause DRESS syndrome. However, antibiotics, allopurinol (anti-gout medication) and anti-epileptic medications are commonly associated with DRESS syndrome. DRESS syndrome typically starts after 2 to 6 weeks of starting a person on the culprit drug.

DRESS syndrome is a condition that is usually managed in the tertiary hospital setting with the involvement of the Dermatology and Immunology/Allergist department. The key step is to stop the culprit medication. Oral or even injection steroid may be used to suppress the allergy reaction and prevent further damage to body organs. The treatment of steroid may be needed for weeks or even up to months, and DRESS patients will need long term to follow up with specialist care.

ADRs: Stevens-Johnson Syndrome & Toxic Epidermal Necrolysis

Steven-Johnson Syndrome (SJS) is a rare, yet potentially fatal skin emergency condition.  SHS can progress into an even more severe form of a condition known as Toxic Epidermal Necrolysis (TEN). Both conditions occur with extensive skin and mucous membrane reaction to a particular medication, or a pre-existing bacterial infection or illness.

Although SJS and TEN can affect any age group, the elderly, people with HIV or Herpes are more at risk.

One can present with flu-like symptoms such as fever, cough, aching, headache, eye burning sensation. This is followed with red to a purplish painful skin rash that spreads quickly over the face and body. The rash subsequently progresses into skin blisters. Blisters can also involve the eyes, mouth and genitals. Skin layers may shed away, giving the appearance of skin being burned.

This is a very severe emergency condition, and one should seek hospital medical attention immediately.

Although Drug Allergies can be unforeseen, especially when a person is taking a new medication, it is important to keep your doctors, dentists and pharmacists updated on any known drug allergies. One should always be constantly vigilant on the symptoms and red flags of Drug Allergies. In doubt, speak to your doctors.

Take care.

From Avoidance to Early Exposure of Allergenic Food

The concept of early avoidance as prevention of future allergy has been challenged over recent years.

The presence of peanut allergy has increased over the past decade in countries that recommend peanuts avoidance during pregnancy, breastfeeding and during the infancy period of the baby. Peanut allergy affects approximately 1.5% of young children and tends to be diagnosed in those aged less than 2 years old.

Two groundbreaking research programs- LEAP and LEAP ON trials

LEAP (Learning Early About Peanut Allergy) is a randomized controlled clinical study performed by the Immune Tolerant Network (ITN) sponsored by the National Institute of Allergy and Infectious Diseases to find ways to prevent peanut allergy in young children. 

The study investigated over 600 children between age 4 to 11 months of age who are high risk for allergy to peanut. The risk severity is based on the history of egg allergy and/or severe eczema. The children are randomly separated into two groups- children who consume peanut-containing snack food 3 times a week, and children who avoid peanuts.

LEAP study revealed 17% of children who avoided peanut developed peanut allergy by the age of 5 years. Interestingly, only 3% of children who consumed peanut snack food developed a peanut allergy by 5 years of age. It showed the effectiveness of preventing peanut allergy by 80% later in life in high-risk infants who continuously consumed peanut beginning of their first 11 months of age in comparison to non-peanut consumers. 

LEAP ON study is a follow-up study from the original LEAP study to investigate whether the children who had consumed peanut for over 4 years had persistent protection against peanut allergy when they stopped eating peanut.  The study followed up 556 children from the original children in LEAP for a one-year period of peanut avoidance. After a year of avoiding peanuts, children from original peanut consumers showed only 4.8% of peanut allergy while 18.6% of the children with original peanut avoidance showed peanut allergy.

Encouraging Early Exposure of Allergenic Food in High-Risk Infants

The findings from LEAP and LEAP ON trials have challenged the old school of thoughts of avoiding allergenic food in early infancy in preventing the development of food allergy. Food guidelines over the world have been revamped, embracing and shifting food allergy concept to encouraging early repeated exposure of a child’s immune system to peanut at an early age, to allow the body to learn, adapt and tolerate peanut.

The Canadian Pediatric Society advises in their food guideline in early 2019 to offer babies with the risk of allergies, common allergenic food such as peanut butter and eggs, around the age of 6 months old, but not earlier than 4 months old.

In the United States, the food guidelines since 2017 have been recommending the introduction of peanuts in the early days of infancy to avoid peanut allergies.

In Singapore, common allergenic foods include eggs, peanuts and shellfish. It is advisable by most paediatricians for commencing common allergenic food between 4 to 6 months of age, and this should not be delayed beyond 6 months of age. Breastfeeding should be encouraged at least up to the first 6 months or even up to a year. Pregnant mothers are not advised to avoid allergenic food as the evidence remains inconclusive in reducing the risk of allergies in children.

Importantly, your children should receive a healthy balanced diet.

Speak to your doctor, or an allergist to find out more.

Allergy Immunotherapy modifies a person’s body immune response towards allergens, hence easing allergy symptoms. Allergy immunotherapy is effective against IgE-mediated allergy, and benefits in particular individuals with a limited type (1 or 2) of allergies.

How is Allergy Immunotherapy delivered to a person?

Allergy Immunotherapy Shots
Immunotherapy shots are delivered via injections in high dosed standardized vaccines containing the allergen every month. Over time, the dose is gradually increased for the body’s immune system to adapt. As there is a risk of unforeseen severe allergic reactions such as anaphylaxis, immunotherapy shots should only be given by a trained doctor or immunologist in a controlled setting clinic with standby resuscitation facilities available. The duration of Immunotherapy shots is usually 3-5 years.

Sublingual immunotherapy (SLIT)
SLIT is emerging as an effective and safe alternative to Allergy Immunotherapy Shots. Furthermore, SLIT has the advantage of self-administration of medication by the patient himself at home.  As the name suggests, sprays or tablets containing allergens are administered under the tongue daily. 

The choice of whether considering immunotherapy shots vs sublingual immunotherapy can be determined by the patient’s preference with prudent guidance from the trained physician.

Who should consider Allergy Immunotherapy?

You can consider Allergy Immunotherapy if you are:

Who are the contraindicated for Allergy Immunotherapy?

You should avoid Allergy Immunotherapy if:

Is Allergy Immunotherapy Effective?

Medical reviews have shown significant improvement in allergy symptoms with immunotherapy, with the reduction in requiring rescue medication, and general improvement of quality of life. Also, immunotherapy has shown long term benefits by modifying the underlying cause of allergy condition. There are several research studies that showed continue long-term benefit of reduction of allergy up to 7-8 years following discontinuation of immunotherapy.

Allergy Immunotherapy is a proven effective treatment for allergic conditions such as allergic rhinitis, asthma, insect sting allergy, and certain individuals with eczema in particularly allergic to airborne allergens such as house dust mite, and animal dander.

Is Allergy Immunotherapy safe?

The limitation of immunotherapy shots lies on the risk of possible systemic allergic reactions, such as anaphylaxis that can be fatal. Risks factors for systemic reactions include a history of previous systemic reactions, the presence of asthma, a history of high sensitivity allergen exposure.

SLIT is a safer option. SLIT is associated with localized symptoms such as itching and tingling of the tongue or mouth, tongue and lip swelling in 50% of patients. The symptoms usually resolve within 1-2 weeks after commencement of treatment.

Allergy Immunotherapy remains a novel, exciting, highly effective and promising area for both trained physicians and patients with allergy, seeking for long term control and remission of allergy. Speak to your doctor to understand further.

What are the Common Causes of Anaphylaxis?

What are the Signs and Symptoms of Anaphylaxis?

Recognizing the signs and symptoms of anaphylaxis are important. This can be life-saving. Involvement in any of the 2 systems of the body should lead to prompt immediate treatment with epinephrine.

Lady suffering from Anaphylaxis

What are the Treatments for Anaphylaxis?




Asthma Inhalers

How can I Prepare and Prevent Anaphylaxis?

Prevention is always better than cure

Prepare and Be Ready

Recognize and Act on Anaphylaxis Promptly

Remember, anaphylaxis is completely reversible if managed promptly. However, any delay in anaphylaxis can be lethal.

Take care, stay safe.

It is useful in allergic respiratory diseases such as allergic rhinitis and asthma. It is suitable for adults, and even children above the age of 2. The medication is administered beneath the tongue.

Why Should I consider Sublingual Immunotherapy (SLIT)?

SLIT Oraltek® Spray

Oraltek® Spray is a type of sublingual Immunotherapy that can be administered via a spray underneath the tongue. It comes in a vial with a spray nozzle containing extracts from particular allergens.

How to Use Oraltek® Spray?

  1. Hold the spray with your dominant hand.
  2. Raise your tongue and direct the nozzle spray underneath your tongue.
  3. Hold the medicated solution in your mouth for 1-2 minutes before swallowing.
  4. Avoid oral intake, mouth rinsing or teeth brushing for the next 15- 30 minutes after administering the medication.
  5. Store the spray well.
  6. Repeat the procedure daily.

Do I Need to Stop Other Allergy Medications when I am on Sublingual Immunotherapy?

You do not usually need to stop your other medications for allergy treatment. However, over time, you may need less of your medications as the sublingual immunotherapy has effectively reduced your allergy symptoms.

If you are concerned with any medications interacting with sublingual immunotherapy, you can speak to your doctor.

Does Oraltek® Spray actually work?

The effectiveness of the treatment correlates with the length of treatment. Good medication compliance promises a better long-run sustaining effect of reduced allergy symptoms or even an allergy cure.

You are expected to see some functional results within the first year of treatment.

You should:

If after one year of treatment, you do not achieve the above end results, you should speak to your doctor to revise the diagnosis and treatment plan.

What are the Risks and Side Effects of Oraltek® Spray?

You may experience temporary side effects such as mild itching, burning sensation or swelling over the administered site. However, as the spray covers a wide surface area of the mouth, the side effects are lesser in comparison on tablets or drops.

If you encounter such symptoms, you should still continue to treat through with the spray, as the symptoms resolve spontaneously with repeated use of the spray.

How long do I need to use Oraltek® Spray? Can I abort the treatment before the recommended time frame?

The recommended duration of treatment is 3-5 years. In the event of you stopping the treatment before 3 years, the effectivity of allergy improvement may not sustain over time.

Where should I keep my Oraltek® Spray?

You are advised to keep the spray in the refrigerator at a temperature of 2-8C. Having said that, the spay is safe and stable at a temperature below 25C.

Any Travelling Tips when on Oraltek® Spray?

It is relatively hassle-free. You are allowed to hand carry when travel by air, and stored it in a small bag with an ice cube.

You should avoid stopping the treatment for more than 1 week. 

Is there are other options of Sublingual Immunotherapy?

Yes, speak to your doctor, there are tablets form as well.

Furthermore, the fur of pets can act as a reservoir for pollen and mould spores. These proteins when coming into direct contact on a person’s skin or being inhaled can behave as allergens to a body’s immune system, triggering allergic reactions. Common allergic medical conditions associated with Pet Allergies include allergic rhinitis, asthma, eczema, and hives.

Contrary to many believe, there are no actual ‘hypoallergenic breeds’ of cats and dogs. The length of the animal’s hair or the amount of hair or fur shed do no determine the allergenic potential.

What are the Symptoms of Pet Allergies?

Pet Allergy symptoms can occur during, and shortly after contact with a pet. The symptoms tend to last long even when the animal is gone. This is because the dander can stay in the air, on the surrounding furniture or on your clothes for a long while.

Common symptoms include:

You may have chronic symptoms discussed above if you are exposed to your pet on a long term basis.

What do I expect when I consult my doctor for Pet Allergies?

Your doctor will obtain the relevant allergy history. Allergy testing in the form of blood tests and skin prick test may be offered by your doctor/ allergist to confirm the allergy.

What are the Treatment Options for Pet Allergies?

As of any type of allergies, avoidance of trigger is key. Often, staying away from your pet is not an option, you may consider symptomatic relievers such as antihistamines, decongestants, and corticosteroids. 

Pet allergy can be a long term concern if you own the pet. Symptomatic relievers may not be an ideal solution. You may consider speaking to your doctor/ allergist for immunotherapy allergy shots as a long term solution.

What can I do to minimize Pet Allergies?

This allergy is common among healthcare workers, people who have undergone multiple surgeries, rubber industry workers, laboratory workers, hairdressers, housekeeping workers, food handlers, and gardeners.

Latex is a watery milky sap that is derived and tapped from rubber trees. It is processed with other chemicals to enhance its elasticity. Rubber latex can be found in rubber gloves, rubber bands, erasers, balloons, and condoms.

In Latex Allergy, the body’s immune system perceives latex as an allergen and triggers a cascade of an allergic reaction. Half of the people with Latex Allergy have an allergy to other common allergies.

What are the Symptoms of Latex Allergy?

The reaction symptoms can range from mild to very severe, including life-threatening anaphylaxis reaction. The severity of Latex Allergy can worsen with repeated exposure of the latex substance as the body’s immune system is sensitized by latex during the past exposure, and recognizes the allergen during subsequent exposures.

Delayed reaction
In this reaction, the allergic symptoms tend to occur 12-36 hours after exposure to latex and manifest as contact dermatitis. One can present with red, itchy and scaly raw skin. The symptoms tend to be localized over the exposed skin area, and they are not life-threatening.

Immediate reaction
This type of allergic reaction occurs in people who have been exposed to latex and the body’s immune system is sensitized to latex and able to recognize the allergen on subsequent exposure, leading to more severe immune responses such as:

In severe life-threatening case, anaphylaxis can occur within minutes of exposure to latex. Anaphylaxis symptoms typically involve more than one body system, with manifestations of:

*Call 995 or seek medical assistance immediately if you suspect anaphylaxis.

What do I expect when I see my doctor for Latex Allergy?

Your doctor will enquire a thorough medical and allergy history. In certain clear cut cases, a history of latex exposure followed by a reaction may suffice to diagnose the allergy. In other cases, your doctor may offer you allergy testing such as skin prick test, patch tests and RAST blood tests to determine your allergy triggers.

What are the Treatment Options for Latex Allergy?

Avoidance is key.
Consider Substitutes:

Mild skin reactions can be relieved with oral antihistamine and topical corticosteroids.

People with anaphylaxis secondary to Latex Allergy to carry auto-injectable epinephrine (Epipen) in case of a severe life-threatening emergency. They should be taught how to self-administer the injection. Those suspected of anaphylaxis should seek medical help as soon as possible to prevent a fatality.

Common insect stings in Singapore come from yellow jackets, hornets, wasps, and honey bees. After stinging human’s skin, the insects leave behind their stingers. The stingers are best removed by a scraping action, rather than a pulling motion to prevent further squeezing of more venom into the affected skin.

The body’s immune system reacts differently towards insect stings. Reactions can range from simple painful swelling and redness to severe life-threatening conditions such as anaphylaxis. A person who has experienced an allergic reaction to insect sting has a 40-60% chance of a similar or even more severe reaction for each subsequent sting.

Picture of an insect sting

What are the Symptoms of AN Insect Sting Allergy?

Most people sustain localized pain, redness, and swelling over the affected area of an insect sting.

In the case of an Insect Sting Allergy, the immune system overreacts to the sting, leading to possible symptoms of anaphylaxis with symptoms involving more than one body system such as:

Insect stings can also cause a toxic reaction. This is not an allergic reaction, rather, the body perceives the insect venom as a poison. Having said that, both toxic reaction and allergy reaction from insect stings can cause similar symptoms in the affected person. In a severe toxic reaction, one can have fainting spells, shock, seizure, or even succumb to the reaction.

What do I expect when I consult my doctor for AN Insect Sting Allergy?

Your doctor will obtain a thorough history of your current and previous stings. It will be useful to inform your doctor about how many stings you have had, the reactions from the stings, and how long the reaction lasted in the past. In certain circumstances, your doctor may offer skin prick tests or blood tests to an insect venom panel.

What are the Treatment Options for Insect Stings Allergy?

It is important to avoid contact with insects in the first place. If you are allergic to insect stings, take precautionary measures against this.

Anaphylaxis and Immediate Treatment
If you have an anaphylactic reaction, please ask for help and call 995 as you will need immediate medical attention. This can be life-threatening. Immediate epinephrine injection can be life-saving. Aside from delivering epinephrine, other emergency medications include antihistamine, corticosteroids, intravenous fluids, and oxygen. Anaphylaxis patients usually need to be admitted to the hospital overnight for observation.

Long Term Treatment with Venom Immunotherapy
This is a form of long term management. It is a procedure done by trained doctors or allergists by the gradual introduction of incremental venom doses to a person. This is with the theory of repeated exposure to the venom will reduce a person’s immune system sensitivity towards the venom, hence reducing the risk of a future allergic reaction.

Immunotherapy in the form of allergy shots is introduced to build tolerance and 97% protection against the future sting. This therapy is particularly useful to those who are active outdoor individuals for both recreational activities or work-related activities.

How can I avoid Insect Sting?

Most insect stings in Singapore are from yellow jackets, hornets, honey bees, wasps.

Here are some tips for sharing:

Once stung, twice shy! Be careful, and avoid insect stings! Take care!