Sounds like an unusual name but I have a few patients on SLITs! So what exactly is SLIT? The acronym stands for Sub Lingual Immuno Therapy! Over the last few years it seems that this has come into the main stream and is being widely prescribed where I practice. I did some quick reading via UpToDate and here were a few highlights that I saw:
- Source article http://www.uptodate.com/contents/sublingual-immunotherapy-for-allergic-rhinitis
- It works – but it is not clear by how much
- Oral therapy should be stopped if there is mucosal ulceration
- Don’t start in pregnant ladies but may continue if already started.
- Duration can be limited i.e. 16w before allergy season or up to 4 years.
- In Jeddah I am aware that Dr Soliman Fakeeh hospital offer a French product called: Staloral® : sublingual solution containing allergen extracts.
- As I am writing this article I came across a European patient who had tried the oral therapy over 20 years ago! He ran into problems with mucosal ulceration when the potency was increased.
- The italicised extracts below are from the UpToDate article on the subject:
- In a 2011 systematic review of 60 randomized trials (published through 2009), which included approximately 2300 adults and children receiving active SLIT treatment, treatment resulted in a statistically significant reduction in symptoms (standardized mean difference of -0.42 [95% CI -0.69 to -0.15]) and in medication requirements (standardized mean difference of -0.43 [95% CI -0.63 to -0.23]) .
- No trial reported anaphylaxis or the need to administer epinephrine.
- Effects on quality of life could not be assessed because a variety of different measurements were used.
- Many study designs have now chosen the clinical outcome of “total combined score” (TCS) as the accepted evaluation tool to measure primary efficacy. However, no standardized scoring methodology has been adopted across the industry for quantification of symptoms and medication use.
- In an attempt to define clinically meaningful improvement, the World Allergy Organization (WAO) has proposed that a 20 percent mean reduction in TCS compared with placebo be demonstrated .
There are two forms of SLIT with inhalant allergens that have been widely studied: dissolvable sublingual tablets (SLIT-tablet) and sublingual allergen extracts (SLIT-drops).
The most consistent results have been obtained with SLIT-tablet formulations.
SLIT has been shown in randomized trials to be effective for allergic rhinitis (with or without conjunctivitis) and safe for patients with concomitant milder asthma. However, efficacy in reducing the symptoms of persistent, not well-controlled allergic asthma has not been conclusively demonstrated.
SLIT has been used in Europe and some other countries for decades for the treatment of allergic rhinoconjunctivitis. The first sublingual products, a five-grass pollen tablet, a single grass pollen tablet, and a short ragweed pollen tablet, became available in the United States in 2014.
SLIT is self administered by patients (or their caregivers) at home, although the initial dose is usually given under medical supervision. A significant percentage of patient experience local application site reactions (eg, oral pruritus, throat irritation, tongue swelling), but systemic allergic reactions are markedly fewer as compared with subcutaneous immunotherapy (SCIT).
SLIT appears to be somewhat less effective than SCIT