Causes

Hay fever refers to symptoms such as runny nose and sneezing caused by an immune response to pollen such as cedar and Japanese cypress that enters the nose, and is also called seasonal allergic rhinitis. Itching, redness, and tears may also occur in the eyes, which is also called seasonal allergic conjunctivitis.

Flying season

※画像は「https://www.ssp.co.jp/alesion/hayfever/calendar/」から引用

Although the timing of pollen dispersal differs from region to region, the above chart shows the dispersal timing of pollen mainly in the Kanto region.

A large amount of cedar pollen is dispersed from February to April, and in March and April, a large amount of cypress pollen is also dispersed. From August, ragweed pollen is scattered in large quantities until early October. Hay fever can be accompanied by house dust, so those with severe symptoms may have perennial allergic rhinitis.

Symptoms and frequency of occurrence

The main symptoms of hay fever and their frequency of occurrence are listed below. Unlike the common cold, fever, headache and sore throat are not seen in hay fever.

SymptomsFrequency of occurrence
Sneezing55.2%
Runny nose57.8%
Nasal congestion44.2%
Itchy eyes50.8%
Redness of the eyes29.3%
Itchy throat21.9%
Excerpts from the Hay Fever Patient Survey Report (issued in December, 2009)

Medications used for hay fever

Antihistamines

When pollen attaches to cells in the nose and eyes, histamine and leukotrienes are released. Histamine and other substances stimulate the nerves and blood vessels in the nose and eyes, causing hay fever. By blocking the H1 receptors to which histamine attaches with antihistamines, hay fever symptoms can be relieved. The most commonly used antihistamines are second-generation antihistamines, and this type of antihistamine is characterized by relatively less drowsiness and immediate effect.
※The following dosage and administration is for adults.

Fexofenadine
(Brand name: Allegra)

Dosage and Administration

One tablet twice a day (60 mg of fexofenadine in one tablet)

Description

Fexofenadine is a typical antihistamine that can be bought without a prescription. It is also an antihistamine that can already be purchased by mail order. It has the advantage of not making you drowsy, so you can get through hay fever without losing your work efficiency. The advantage is that it has less sedative effect (drowsiness), so much so that even airplane pilots are allowed to take it. A little-known fact is that taking Fexofenadine with high-fat foods  or fruit juices (apple or orange juice) will reduce the absorption rate, making it harder for the drug to work.

Epinastine
(Brand name: Alesion)

Dosage and Administration

Once a day, one tablet (Epinastine 20mg in one tablet)

Description

It is an antihistamine that can be taken once a day. It is more effective than fexofenadine. It also causes drowsiness in some people. If you take it only at night before going to bed, you can get through hay fever, so it is recommended for busy people. Generic versions of Allegion are also available over-the-counter, making it more economical. Another advantage is that it can be used in regular doses even if you have kidney problems.

Cetirizine
(Brand name: Zyrtec)

Dosage and Administration

One tablet once a day (Cetirizine 10mg in one tablet)

Description

This is a drug that works well once a day. It also causes drowsiness, but it is more moderate than Allelock (see below). The successor drug is Xyzal. If you have had little success with this drug, you can try cetirizine once. There is also an over-the-counter drug available for the same effect. If you have any questions, please do not hesitate to contact our pharmacist.

Olopatadine
(Brand name: Allelock)

Dosage and Administration

One tablet twice a day (Olopatadine 5mg in one tablet)

Description

It’s a second generation antihistamine that works well, and although it is a bit prone to drowsiness, it is quite inexpensive, and if you don’t have any side effects, it is quite economical.

Other Antihistamines

Loratadine (Claritin), Evastin (Evastel), and Bepotastin (Tarion) can be purchased without a prescription.

Levocetirizine (Xyzal), Desloratadine (Desarex), Virastin (Viranoa), and Rupatadine (Rupafin) are prescription drugs that require a prescription and are more effective and less drowsy. If you use fexofenadine, nasal drops, and eye drops properly, antihistamines that require a prescription are often unnecessary.

In addition, there are three systems of antihistamines: 1) tricyclic, 2) piperidine skeleton, and 3) piperazine skeleton (2) and 3) are almost identical). Epinastine (Alesion) is classified as a tricyclic drug, and if epinastine is not suitable for you, cetirizine (Zyrtec), which has a piperidine skeleton, may be effective. On the other hand, loratadine (Claritin) has the same tricyclic skeleton as epinastine (Alesion), so it is thought to have the same results as Alesion. Of course, the same system has different effects and drowsiness, so we will talk to each patient and prepare medication according to their symptoms. The following is a skeletal classification of typical antihistamines

Anti-leukotriene drugs

If the nasal congestion is severe, consider anti-leukotriene drugs. Leukotrienes are chemical messengers that dilate blood vessels and cause nasal congestion. They are more effective than antihistamines for nasal congestion and do not have the side effect of drowsiness. Leukotrienes can also increase airway inflammation and cause bronchial asthma, so anti-leukotriene drugs are also used as bronchial asthma preventive drugs.

Pranlukast
(Brand name: Onon)

Dosage and Administration

One tablet twice a day (225mg of pranlukast in one tablet)
※There are two types: tablet type and capsule type.

Description

It is a type of hay fever medicine that can be used together with antihistamines. It can be taken twice a day. It is effective for nasal congestion, so it is recommended for people with severe nasal congestion. The ingredients do not make you drowsy. It can be used in combination with antihistamines at a higher cost, but it can be very effective. Some people develop sinusitis from nasal congestion, so if you have a hard time with nasal congestion during peak hours, consider using this product.

Montelukast
(Brand name: Kipres / Singulair)

Dosage and Administration

One tablet once a day (Montelukast 10mg in one tablet)

Description

It is a type of hay fever medication that can be used together with antihistamines. Unlike pranlukast (Onon), it is effective for nasal congestion once a day. The ingredients do not make you drowsy.

Nasal Drops and Eye Drops

Nasal congestion and itchy eyes can be relieved with nasal and eye drops. For nasal drops, topical steroids are less drowsy and can control hay fever at its peak quite effectively. Regarding eyedrops, there are restrictions on their use for users of 2-week or longer soft contact lenses, so please check the “Soft Contact Lens Classification” group in the package insert of the brand you are using.

Fluticasone
(Brand name: Flunase)

Dosage and Administration

One spray in each nostril twice a day (50 μg of fluticasone)

Description

It is a nasal spray that contains steroids. There is no problem in using steroids topically. It does not cause drowsiness and can improve runny nose, nasal congestion, and sneezing. It would be safer to consider fluticasone (Flunase) first before using drowsy antihistamines.

Ketotifen ophthalmic solution
(Brand name: Zaditen ophthalmic suspension)

Dosage and Administration

The usual dosage is one to two drops four times a day (morning, noon, evening and before bedtime).

Description

It is an eye drop containing ketotifen, an antihistamine. It suppresses itchy eyes, but because it contains benzalkonium as a preservative, it should be used after removing soft contact lenses if you fall into Group III or IV of the soft contact lens classification. In the case of Group I and II, since they are non-ionic and benzalkonium is not adsorbed, they can be used as is.

Alesion Ophthalmic Solution

Dosage and Administration

The usual dosage is one to two drops four times a day (morning, noon, evening and before bedtime).

Description

This ophthalmic solution contains epinastine, an antihistamine. Since it does not contain benzalkonium as a preservative, it can be used while wearing soft contact lenses. The advantage is that you don’t have to think about the compatibility of soft contact lenses, but depending on the classification, some of them may not work if you wear them, so the pharmacist may ask you about the brand and recommend other eye drops.

Other Nasal and Eye Drops

Nasal drops include ketotifen nasal spray and pribina solution. Nasal drops that require a prescription include Alamyst and Nasonex.

Eye drops include Patanol ophthalmic solution, Rizaben ophthalmic solution, and Flumetron ophthalmic solution.