Skin Prick Allergy Test in Singapore

A single allergen is $54.50. The 12-allergen skin allergy package is $490.50, which works out cheaper than testing the same twelve separately (that would be $654.00). A doctor consultation from $49.05 is required first, because which allergens are worth testing comes out of your history.

Testing a long list is not automatically better. Two or three well-chosen allergens that match your symptoms usually tell you more than twelve chosen at random.

Allow 30 to 60 minutes in total. The pricks themselves take a couple of minutes; most of the appointment is the consultation beforehand and the 15 to 20 minute wait while the skin responds.

You get your results in the same visit — a doctor measures the reactions and goes through what they mean before you leave. There is no separate results appointment.

It is uncomfortable rather than painful. A drop of each allergen is placed on the forearm and the surface of the skin is pricked through the drop with a small lancet — it does not draw blood and it is not an injection.

Where you do react, the spot becomes itchy and raised for a while. That settles on its own, usually within an hour or two, and the itch can be treated afterwards if it is bothering you.

Very rarely the reaction spreads beyond the test site and needs treating — around 77 in every 100,000 people tested, so well under one in a thousand. That is why testing is done in a clinic rather than at home, and why someone who has had anaphylaxis before is usually tested by blood first.

Antihistamines are the main one — they suppress the skin's response and can turn a real allergy into a negative result. We ask you to stop them for one week beforehand. That covers cetirizine, loratadine, fexofenadine, chlorpheniramine, diphenhydramine and triprolidine, including antihistamines inside combined cold and flu remedies. Antihistamine nasal sprays and eye drops matter less — a couple of days is enough for those. Steroid creams applied to the test area need to stop for at least three days. Steroid tablets do not need to be stopped — they do not affect the result, and stopping them abruptly can be harmful.

Tell us before you book if you take beta-blockers, tricyclic antidepressants such as imipramine, or phenothiazines, or if you are having UV light therapy — these need a decision rather than a blanket rule. Beta-blockers are worth naming specifically: they do not change the result, but they can blunt the response to adrenaline if a reaction ever needs treating. Never stop a prescribed medicine on your own; check with us first, and if coming off antihistamines is not realistic, a blood test measures the same allergies without any washout.

A reaction is measured, not just eyeballed. Each site is compared against two controls placed on the same arm: histamine, which should produce a reaction and confirms your skin is responsive, and saline, which should not. By European standards for skin prick testing, a raised wheal of 3 mm or more across, read at 15 to 20 minutes, counts as positive.

A bigger wheal means more sensitisation, but it does not directly predict how severe a reaction would be. That is why the result is read against your history rather than on its own.

Neither is better across the board; they answer the same question in different ways. Skin prick gives you an answer in the same visit and costs less per allergen, which suits a short, focused list. A blood test needs no medication washout, is unaffected by eczema or dermographism, tests many allergens from one sample, and is preferred if you have ever had a severe reaction.

Your doctor will advise which fits your history. Sometimes the answer is both, or one after the other.

Yes. It is done in children and is often easier for them than a blood draw, because there is no needle into a vein and the result comes back the same visit.

The same medication rules apply, and children's antihistamine syrups count. If a child cannot manage staying still for the wait, or their eczema covers the usual test area, blood testing is the practical alternative.

It is not suitable for everyone. Widespread eczema or a rash over the forearms and back leaves nowhere clean to test. Dermographism — skin that weals when it is scratched — produces reactions everywhere and makes the result unreadable. Someone who cannot stop antihistamines, or who has had a severe reaction such as anaphylaxis, is usually tested by blood instead.

Tell us if you take beta-blockers or are pregnant so we can decide the safer route — with beta-blockers the concern is that they blunt the response to adrenaline if a reaction needs treating, not that they alter the reading. In each of these situations the allergy can still be investigated — just with a blood sample rather than through the skin.

Not on its own. A positive result shows sensitisation, meaning your immune system recognises that allergen. Plenty of people are sensitised to something they eat or meet with no trouble at all.

It becomes a diagnosis when the result matches what actually happens to you — what you were exposed to, how quickly symptoms came on, and whether it has happened more than once. A positive that does not fit your story is a reason to discuss it, not to start avoiding that food or animal.