New Treatments: Helminth Therapy

Hookworm

In November of 2010, a study was conducted by researchers Endara, Vaca, Chico, Erazo, Oviedo, Quinzo, Rodriguez, Lovato, Moncayo, Barreto, Rodrigues and Cooper from the Colegio de Ciencias de la Salud at the Universidad San Francisco de Quito and published in the Journal of the British Society for Allergy & Clinical Immunology. The study focused on the effect of anti-helminth treatments on the prevalence of allergies. Helminths are parasitic worms that need the resources of a host body to survive. Researchers have been experimenting with helminth therapy or the intentional inoculation of patients with helminths, for quite some time now. The theory behind helminth therapy is that our body's immune system is naturally regulated by the presence of these helminths. As part of their survival, these parasites down-regulate the part of the host's immune system that is also responsible for the auto-immune and allergic responses. However, modern society has become so "clean" that many of these parasites can no longer survive. Some theorize that the lack of natural parasites has screwed up the immune system, resulting in an increased incidence of auto-immune diseases and allergies.

Obviously there are many helminths that are so dangerous that their presence would threaten our health, but some are relatively safe. For example, low concentrations of hookworms and whipworms are not considered a real health hazard. Therefore, these "weaker" helminths have been experimented with in helminth therapy. By introducing hookworms or whipworms into patients with auto-immune diseases and severe allergies, the immune system may work itself out. In the case of allergies, this means that the body will no longer respond to an allergen. For example, the binding of pollen to the IgE antibody will no longer activate the mast cells and induce the release of histamine and other mediators. In other words, the body becomes desensitized to the allergen.

Whipworm

In the study, researchers performed an allergen skin test on school-aged children from two different communities, to determine their reactivity to the allergen. The children of one community received the anti-helminth treatment, ivermectin, for fifteen to seventeen years, while the children of the other community did not. The researchers found that twice as many children receiving ivermectin experienced an allergic response to the skin test (16.7%), compared to the children who hadn't received anti-helminth therapy (8.7%). For children treated with ivermectin, the results show a statistically significant increase in the number of those with allergies. However, it is unclear whether other factors were accounted for. For example, the incidence of second-hand smoke or pollution may have been greater in the community giving ivermectin treatments, which may have accounted for the increased incidence of allergies in the population. Either way, helminth therapy will definitely prove to be very controversial.  

Where do we drawn the line? Helminth therapy may reduce the severity of auto-immune diseases and allergic reactions, but is the danger associated with helminth therapy worth the risk? More research needs to be done, especially on the long-term risk of using this treatment. However, if helminth therapy does prove to be effective and safe in the long run, are people really going to be willing to infect themselves with a parasite? Only time will tell whether helminth therapy will become the new treatment or fade from view.

For more information about Helminth Therapy Click Here

For a more in-depth look at using parasites, take a look at the blog Waiting For The Cure, which chronicles one person's use of parasitic worms to treat Crohn's Disease

To view a Live Science article about Helminth Therapy Click Here

New Treatments: Targeting Neuropeptides

NPY

In January of 2011, a study was conducted by researchers Sacchetti, Micera, Lambiase, Speranza, Mantelli, Petrachi and Bonini from the Department of Ophthalmology at the University of Rome and published in Molecular Vision. The study focused on the role of neuropeptides in the inflammatory response associated with allergic conjunctivitis. Neuropeptides are molecules that work with mediators to increase or decrease their effects. For example, when the neuropeptide NPY is released in conjunction with norepinephrine, it amplifies the vasoconstriction or squeezing of blood vessels produced by norepinephrine. In the case of allergies, neuropeptides may play a role in increasing the effects of mediators used in the inflammatory response. For example, neuropeptides may be released along with histamine, producing an increased inflammatory response that would not be seen if histamine were released by itself.

In the study, researchers sought to measure levels of neuropeptides in the tears of patients with allergic conjunctivitis and those without. If there were more neuropeptides in the tears of allergic conjunctivitis patients, it is likely that neuropeptides play a role in the inflammatory response. A conjunctival provocation test (CPT) was used to measure the allergic response of fifteen patients with allergic conjunctivitis and ten patients without allergic conjunctivitis. This served as a control because the patients with no allergic response should have a very low CPT score. Then tear samples were collected from all patients and the amount of neuropeptides VIP, NPY, CGRP and SP were measured.

The researchers found that the concentration of VIP, CGRP and SP neuropeptides were higher in the tears of allergic conjunctivitis patients. However, there was no significant difference in the number of NPY neuropeptides in the allergic conjunctivitis and non-allergic patients. However, this evidence suggests that neuropeptides may play a role in increasing the effects of mediators involved in the inflammatory response. More research needs to be done to identify that role. If researchers succeed, this opens up another avenue for treatment. For example, inhibiting the binding of neuropeptides or blocking their release, can decrease the effects of neuropeptides and maybe decrease the effects of inflammatory mediators like histamine. It will be interesting to see how this area of research develops in the future.

If you are looking for a new way to approach allergic conjunctivitis, discuss recent developments in neuropeptide research with your healthcare provider. 

New Treatments: Alcaftadine vs. Olopatadine

In February of 2011, a study was conducted by researchers Ono and Jane from the Dobbs Ocular Immunology Laboratories of Emory University School of Medicine & Emory Eye Center and published in Drug Design, Development & Therapy. The study focused on the role of conjunctival tight junctions in the allergen-induced inflammatory response. The tight junctions of the conjunctiva epithelium serve as a barrier to prevent the allergen from entering the conjunctiva and eliciting an immune response. If you remember, the epithelium is similar to a liner, keeping unfavorable things out of the conjunctiva. In people with seasonal allergies, they seem to express a lower level of proteins used to create these tight junctions; less tight junctions results in more allergens breaking through. Also, many allergens have enzymes that can be used to force entry into the conjunctiva.

Enzymes are a type of protein with many different functions. The function of the enzyme depends on what type it is; there are thousands of enzyme types that have been identified. In the case of allergens, they contain a type of enzyme that can breakdown the tight junctions in the epithelium, allowing the allergen to pass through. For example, enzymes from pollen and house dust mite feces have been shown to degrade the junctions, making the conjunctiva more permeable to the allergen. If you remember, once the allergen enters the conjunctiva, it binds to the IgE antibody on the mast cells, stimulating the release of histamine and other mediators to elicit the allergic reaction.

In the study, researchers compared the effect medications alcaftadine and olopatadine on the conjunctival tight junctions. Eighty mice were used in the study. They were broken up into five groups, consisting of sixteen mice each. Each of the five groups were subjected to a different portion of the study. Overall, the goal was to determine which medication, alcaftadine or olopatadine, had a greater efficacy.

The results showed alcaftadine to have a greater anti-histamine effect than olopatadine. More importantly, alcaftadine had a protective effect on the tight junction. Alcaftadine seemed to prevent allergen-initiated breakdown of the tight junctions, decreasing the number of allergen molecules that passed through the conjunctiva. Although the actual mechanism of action is unknown,  the ability of a drug to affect the tight junctions opens up a new avenue of research for allergic conjunctivitis therapy. 

For more information about alcaftadine (Lastacaft) Click Here

For more information about olopatadine (Patanol) Click Here

New Treatments: Local Conjunctival Immunotherapy

In December of 2010, a study was conducted by researchers Kasetsuwan, Chatchatee and Reinprayoon from the Allergy & Immunology Society of Thailand and published in the Asian Pacific Journal of Allergy & Immunology. The study focused on the use of local conjunctival immunotherapy (LCIT) to desensitize patients to the allergen. We know that a person with allergic conjunctivitis has an allergic, inflammatory response when an allergen binds to the IgE antibody. If you remember, the binding of antigen to the IgE activates the mast cells to release histamine and other mediators to induce the inflammatory response. In immunotherapy, patients receive an antigen dose low enough that it doesn't elicit an immune response, but the body is stimulated into producing more antibodies against the antigen. With each increasing dose of antigen, the body's immune response becomes desensitized to the antigen. In other words, under normal antigen exposure, the body is less likely to elicit an immune response, effectively decreasing the allergic response.

In the study, researchers synthesized allergen extracts in eye drops, which they gave to nine out of the eighteen patients. The other nine patients served as the control group, receiving salt solution eye drops that had no therapeutic effect. The two groups of patients were given their respective eye drops once daily for six months. All subjects enrolled in the study must have exhibited an allergic reaction to house dust mites via a skin prick test.

To determine the efficacy of the LCIT, the researchers used a conjunctival provocation test (CPT). This test is representative of the immune response to an allergen; a lower CPT score means a reduced allergic reaction. The results of the study showed a significant reduction in CPT scores for the experimental group receiving the allergen extract eye drops, compared to the control group. However, when comparing symptoms of the allergic response, there proved to be no significant difference between the experimental and control group. What does this mean?

Although the LCIT works in theory, it may not work in reality. This is often the case for many treatments; they look great on paper and should work, but when applied to real human models, they prove ineffective. However, the fact that CPT scores were reduced, means that the researchers must be on to something. There was no alleviation of symptoms, but that doesn't mean that immunotherapy should be ruled out. This was only one study and there has been a lot of research and buzz around allergen immunotherapy; it may be the future of allergic conjunctivitis. If you are interested in immunotherapy as a solution to your allergic conjunctivitis, contact a certified allergist.   

For more information about immunotherapy, visit the Mayo Clinic and the American Academy of Allergy Asthma & Immunology.

Current Meds: Advil

How It Works: Advil is a systemic NSAID that decreases inflammation throughout the body. It inhibits the synthesis of a mediator called prostaglandin, which is responsible for causing the sensation of pain. Advil also produces vasoconstriction to shrink the blood vessels to decrease swelling.

Common Side Effects: Advil may cause dizziness, diarrhea, constipation, heartburn, nausea and stomach pain. If you experience an allergic reaction, dark stools, chest pain, confusion, dark urine, depression, fainting, fast heartbeat, arm/leg numbness, peeling skin, severe vomiting, bruising, bleeding or unusual joint/muscle pain, seek medical attention immediately.

*To evaluate Advil Click Here

Current Meds: Acular

How It Works: Acular is an ophthalmic NSAID that decreases inflammation in the eye. It produces vasoconstriction, which shrinks the blood vessels in the eye, decreasing infiltration of fluid and white blood cells into the conjunctiva. There is also a decrease in pain and redness caused by enlarged blood vessels.

Common Side Effects: Acular may cause eye irritation, blurred vision, headache, stinging and burning when applied. If you experience an allergic reaction, persistent pain, bleeding, vision changes or an eye infection, seek medical attention immediately.

*To evaluate Acular Click Here

Current Meds: Alamast

How It Works: Alamast is a mast cell stabilizer, so it inhibits release of mediators from mast cells that are involved in the inflammatory response.

Common Side Effects: Alamast may cause dry eyes, burning or stinging in the eyes, headache, sneezing and runny nose. If you experience an allergic reaction or fever, seek medical attention immediately.

*To evaluate Alamast Click Here

Current Meds: Alocril

How It Works: Alocril is a mast cell stabilizer, so it inhibits release of mediators from mast cells that are involved in the inflammatory response. For example, the release of histamine is prevented, so there is decreased swelling, redness, itchiness and pain.

Common Side Effects: Alocril may cause changes in taste, headache, stuffy nose and burning or stinging of the eyes. If you experience an allergic reaction, coughing, wheezing or difficulty breathing, seek medical attention immediately.

*To evaluate Alocril Click Here

Current Meds: Pred Forte

How It Works: Pred Forte is an ophthalmic corticosteroid that is believed to inhibit enzymes in the eye that are involved in the inflammatory response.

Common Side Effects: Pred Forte may cause blurred vision and stinging or burning in the eyes. If you experience an allergic reaction, changes in vision, persistent itching or discharge from the eyes, seek medical attention immediately.

*To evaluate Pred Forte Click Here

Current Meds: Lotemax

How It Works: Lotemax is an ophthalmic corticosteroid that is believed to inhibit enzymes in the eye that are involved in the inflammatory response. It decreases swelling, migration of white blood cells to the site of the allergen, pain and other symptoms associated with the inflammatory response.

Common Side Effects: Lotemax may cause blurred vision, discharge from the eyes, dry eyes, headache, tearing-up, runny nose, sensitivity to light and stinging when placed in the eye. If you experience an allergic reaction, persistent itching, distorted vision and eye pain, seek medical attention immediately.

*To evaluate Lotemax Click Here

Current Meds: Allegra

How It Works: Allegra a systemic anti-histamine, so it blocks the function of histamine throughout the body.

Common Side Effects: Allegra may cause back pain, dizziness, headache and upset stomach. If you experience an allergic reaction, earache, fever, vomiting or severe/persistent cough, seek medical attention immediately.

*To evaluate Allegra Click Here

Current Meds: Benadryl Allergy

How It Works: Benadryl is a systemic anti-histamine, so it blocks the function of histamine throughout the body. It also decreases nausea, vomiting and motion sickness.

Common Side Effects: Benadryl may cause dizziness, drowsiness, thickening of mucous in nose/throat and dry mouth, throat and nose. If you experience an allergic reaction, fast heartbeat, hallucinations, tremor or wheezing, seek medical attention immediately.

*To evaluate Benadryl Allergy Click Here

Current Meds: Zyrtec

How It Works: Zyrtec is a systemic anti-histamine, so it blocks the function of histamine throughout the body.

Common Side Effects: Zyrtec may cause drowsiness, dry mouth and stomach pain. If you experience an allergic reaction, dark urine, fainting, fast heartbeat, mood changes, dizziness, bruising or yellow skin/eyes, seek medical attention immediately.

*To evaluate Zyrtec Click Here

Current Meds: Visine-A

 How It Works: Visine-A contains two active ingredients, naphazoline and pheniramine. The redness associated with allergic conjunctivitis is due to inflammation or dilation of the blood vessels in the eye. Naphazoline is a vasoconstrictor, so it causes the blood vessels to shrink and clears the redness from the eye. Pheniramine is an anti-histamine, so it blocks the function of histamine in the eye.

Common Side Effects: Visine-A is relatively safe. You may experience a tingling sensation. It bypasses systemic side effects.

*To evaluate Visine-A Click Here

Current Meds: Optivar

How It Works: Optivar is an ophthalmic anti-histamine, so it blocks the function of histamine in the eye. It also inhibits other mediators involved in the allergic reaction, such as leukotrienes and PAF.

Common Side Effects: Optivar may cause a bitter taste, blurred vision, headache and burning or stinging eyes. It bypasses systemic side effects.

*To evaluate Optivar  Click Here

Current Meds: Zaditor

How It Works: Zaditor is an ophthalmic anti-histamine, so it blocks the function of histamine in the eye. If you remember, histamine is responsible for inflammation when an allergen is detected. Zaditor also functions as a mast cell stabilizer, so it suppresses the release of mediators from mast cells, preventing the inflammatory response.

Common Side Effects: Zaditor may cause burning eyes, dry eyes, eye discharge, headache, itching, red eyes, sensitivity to light, sore throat, stinging and tearing-up. By using eye drops as opposed to a systemic anti-histamine, you avoid other side effects throughout the rest of the body. If you experience an allergic reaction (characterized by rash, difficulty breathing, tightness in chest, swelling of mouth, lips, face and tongue) or eye pain, seek medical attention immediately.

*To evaluate Zaditor Click Here

Pharmacological Treatments

 Ophthalmic Anti-Histamines

- Zaditor (Ketotifen Fumarate)

- Optivar (Azelastine Hydrochloride)

- Emadine (Emedastine Difumarate)

- Livostin (Levocabastine Hydrochloride)

- Visine-A (Naphazoline/Pheniramine)

- Visine A.C. (Tetrahydrozoline/Zinc Sulfate)

- Patanol (Olopatadine Hydrochloride)

Systemic Anti-Histamines

- Claritin (Loratadine)

- Zyrtec (Cetirizine Hydrochloride)

- Benadryl (Diphenhydramine Hydrochloride)

- Allegra (Fexofenadine Hydrochloride)

- Atarax (Hydroxyzin Hydrochloride)

- Brovex (Brompheniramine Maleate)

- Clarinex (Desloratadine)

- Dytan (Diphenhydramine Hydrochloride)

- Optimine (Azatadine Maleate)

Opthalmic Corticosteroids

- Pred Forte (Prednisolone Acetate)

- Lotemax (Loteprednol Etabonate)

- Durezol (Difluprednate)

- Econopred Plus (Prednisolone Acetate)

- Flarex (Fluorometholone Acetate)

- Vexol (Rimexolone)

 Mast Cell Stabilizers

- Alomide (Lodoxamide Tromethamine)

- Alocril (Nedocromil Sodium)

- Opticrom (Cromolyn Sodium)

- Alamast (Pemirolast Potassium)

Ophthalmic Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)

- Acular (Ketorolac Tromethamine)

- Nevanac (Nepafenac)

Systemic Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)

- Advil (Ibuprofen)

- Aleve (Naproxen Sodium)

Non-Pharmacological Treatments

In the case of a moderate allergic reaction, some may opt out of using medications and simply cope with the symptoms until the immune response has ceased. There are a variety of non-pharmacological treatments that can help relieve the symptoms until the inflammation has subsided.

Marigold

A cool water compress will help soothe the pain and may partially reduce inflammation via vasoconstriction or shrinking of blood vessels. A flax seed and water compress may produce even better results, as flax seed has been shown to reduce inflammation, among other benefits. You can also try a marigold and water compress, which is believed to have
anti-inflammatory properties as well.

Saline Wash

A saline or boric acid wash can be used to flush the allergens out of the eyes. This method is especially effective shortly after exposure. However, once the allergic reaction has set in, the wash may only provide a soothing effect.

Artificial Tears

Lubricating drops or artificial tears can be used to relieve itchiness and burning. However, further irritation may occur, so use sparingly and stop if the condition worsens. 

Chamomile

Chamomile tea bags can also be cooled and placed over the eyes. The active components of chamomile include quercetin and apigenin, which are believed to block histamine release from mast cells, reducing the inflammatory response.

If non-pharmacological treatments are ineffective, different classes of medications have successfully been used to treat allergic conjunctivitis.

Preventing Allergic Conjunctivitis

It is difficult to prevent allergic conjunctivitis triggered by seasonal allergens. However, there are steps that can be taken to reduce the amount of exposure. The simplest precautions can be taken to avoid conjunctivitis, such as withhold from rubbing or touching your eyes unnecessarily. Try to limit time spent outside, especially in parks or densely pollinated areas. Avoid wearing the same clothing, such as a favorite pair of jeans or a sweatshirt, from day to day without washing because allergens can cling to the material. Wearing glasses as opposed to contacts can decrease the amount of allergens, such as pollen, that stick to the contacts and irritate the conjunctiva. If contacts are necessary, be sure to clean them regularly to remove any allergen build-up. Any other measure that limits exposure will aid in preventing the inflammatory response.


In terms of non-seasonal allergens, the same principles of reducing exposure apply. Smoke-induced allergies can be prevented by avoiding second-hand smoke. For example, if staying in a hotel, request a room far away from smoking areas. Stop using cosmetics, hairspray, cologne and perfume that triggers allergies. Try using formulations labeled hypoallergenic because they are less irritating.

Tackling pet dander and dust mites can seem like a daunting task, but maintenance measures are the key to keeping these allergens at bay. Regularly cleaning your house will reduce the level of pet dander and dust mites. Be sure to use wet cloths or a cleaning spray to dust, as this will catch the allergens instead of pushing them into the air. Opting for hard wood and other flooring as opposed to carpet can aid in cleaning because the dust mites have nothing to cling to when vacuuming. Using an air purifier will filter the allergens out of the air. Lowering the temperature and decreasing humidity by using a dehumidifier will create an unfavorable environment for the dust mites. Specific dust mite killers are also available in sprays, which can safely eliminate them from anywhere in your home.

Brushing reduces pet dander

Brushing and washing your pet regularly can reduce the amount of dander released into the home. Designate a place, preferably your bedroom, where your pet is not allowed; this will help in reducing dander exposure, even during sleep. Be sure to wash clothes, bedding and any other materials regularly to remove the pet dander and dust mites.

Don't be discouraged if you still experience symptoms, even if you followed all of these recommendations. It only takes a few tiny particles to trigger an allergic response, but by making these preventative measures part of a routine, the level of exposure will decrease and your general health will improve. If these measures don't prevent allergic conjunctivitis, you may want to try relieving symptoms through non-pharmacological treatments before moving on to medications.

Symptoms Of Allergic Conjunctivitis

Swollen eyelids is a common symptom

The most common symptoms include swollen eyelids, redness, soreness, itchiness, burning, watering discharge and tearing-up. These symptoms can usually be treated by over-the-counter medications. If they become more severe or unbearable, it is a good idea to consult a physician, who can prescribe more powerful prescription medications.

Allergic conjunctivitis is often associated with other symptoms related to general allergies, such as wheezing, sneezing, coughing and runny nose. Therefore, the presence of other allergy symptoms is a good indication of allergic conjunctivitis and not some other eye disorder. If unsure, consulting a health care professional is the safest bet.

Rarer symptoms include severe/shooting pain in the eye, sensitivity to light, intense redness and blurred or distorted vision. If any of these symptoms occur, consult a health care professional immediately.

*Allergic conjunctivitis is noncontagious, so there is no chance of spreading this condition to others

Common Causes Of Allergic Conjunctivitis

 Although seasonal allergens, such as ragweed and other pollens, remain the
primary reason  for the majority of allergic conjunctivitis cases,
there are many other causes:

Smoke                           Pollution                         Cosmetics

Cologne/perfume            Pet dander                      Dust mites

                       Medications                    Cleaning agents               Chlorine               

                       Gasoline                         Hairspray                         Foods

What Is Allergic Conjunctivitis?

Allergic conjunctivitis is the inflammation of the conjunctiva due to an allergen. 

Right eye exhibiting characteristic redness

Allergic conjunctivitis is a Type I hypersensitivity, commonly referred to as an allergic reaction. It is one of the four types of immune responses. The body is "tricked" into thinking an allergen is a threat, such as invading bacteria or viruses. Therefore, the body mounts an immune response to attack and destroy the allergen. The basic pathophysiology is as follows:

- In addition to many other types of cells, the eye contains immune cells called mast cells
- Mast cells have a type of antibody on their surface, called immunoglobulin E (IgE)
- When the conjunctiva is exposed to an allergen, the mast cells' IgE binds to the allergen
- The mast cells become activated and release different mediators to aid in destroying the allergen

Process of histamine release from mast cells

3 Major Mediators Released By Mast Cells

- Histamine: increases vasopermeability or the space between cells of the blood vessels innervating the conjunctiva, so fluid and white blood cells can enter the conjunctiva and destroy the allergen
- Serotonin: increases vasopermeability by the same mechanism as histamine
- Chemotactic Factors: signal the different types of white blood cells to migrate to the site where the allergen was detected, in order to destroy it

*The actions of these mediators and the consequent white blood cells result in the various symptoms associated with allergic conjunctivitis

What Is Conjunctivitis?

Conjunctivitis is the inflammation of the conjunctiva. It is the most common eye disease, easily recognizable by the redness that occurs, justifying the nickname "pink eye"

There are 5 major causes of conjunctivitis:

- Infection caused by viruses, bacteria, parasites or fungi

- Chemical irritation, such as chlorine and smoke

- Skin disorders, such as acne, psoriasis and Stevens-Johnson syndrome

- Systemic disorders, such as Vitamin A deficiency

- Allergies