Researchers at Creighton University have developed a new antihistamine that blocks the H3 histamine receptor. The new drug that blocks H3 is called by its research name – PF-03654746. It’s an exciting discovery because it appears to be the first antihistamine that reduces congestion.
Up until now the only way to reduce nasal congestion was to take an antihistamine/decongestant combination such as Allegra-D or Zyrtec-D. These drugs contain Sudafed, which works, but brings the potential issues of causing insomnia and raising blood pressure. Additionally, taken on a daily basis the body eventually becomes tolerant of its effects and the congestion comes back. Furthermore, because Sudafed can be used to make street drugs it has become closely controlled by the government.
This new antihistamine doesn’t raise blood pressure, cause insomnia or lead to tolerance. It seems to treat congestion by blocking the H3 receptors found in nerves in the nasal membranes. Blocking the H3 on the nasal nerves keeps blood vessels from being engorged and leading to tumescence (i.e. nasal congestion). Clinical trials done with the drug have shown it to be safe and effective. Hopefully, FDA approval will be forthcoming.
(There are currently four known histamine receptors in the human body numbered 1 through 4: H1 blockers are well known and include Benadryl, Allegra, Claritin, Zyrtec and others. H2 blockers are also known and numerous and include Zantac, Pepcid, Tagamet and Axid. H4 blockers are still an early research topic.)
Bucking waves, currents and winds made a really tough task for the athletes competing in the 2013 World Paddleboard Championship in Hawaii even tougher. But our favorite relay team of Dr. Patrick and Dr. Steve Klemawesch beat the elements and finished the 32-mile, open-ocean stand-up paddleboard competition in July.
The crossing in open Pacific waters begins on Kaluakoi Beach on the north shore of Molokai and finishes in Maunalua Bay on the south shore of Oahu. Competing as a team for the first time, the docs finished in – try to grasp how grueling – 6:48:57! Not exactly like doing laps at North Shore Pool! Tropical Storm Flossie threatened to sink the whole endeavor, but held off long enough to let the race follow its schedule.
Good for you, guys!
• Elemental silver has been used for centuries for its antimicrobial properties. In the Middle Ages it was successfully used to treat syphilis, TB and other infections. It is still available today, but caution should be used because excessive doses of silver tonics available over the counter can be toxic to internal organs.
Reprinted and updated from Allergic Reaction, Vol. 1, No. 1, July, 1990
Dear Docs: Your staff asks patients and visitors not to wear perfume or other scented products
while visiting the office. Why is that? “The reason we ask people visiting our office not to wear them is because some of our patients are extremely sensitive to certain scents, including those in some perfumes and colognes, or to the petrochemical base used in these compounds to control their slow evaporation.
“We’re sure you’ll agree it just wouldn’t be considerate to wear a fragrance that might cause a severe reaction to someone else while you’re both here. Some people we’ve seen as patients can’t even go to church due to their sensitivity to perfume. “An allergist’s office is a sensitive environment, filled with sensitive people, and this is one of the things we can collectively work to control. That’s why we ask for the ‘sacrifice’ on your part – and it is appreciated!”
P.S. From that same 1990 issue: A Q(uick) Tip mentioning that magazines at that time had begun offering scent-free subscriptions. Readers could call to request a spot on the “allergy” list of subscribers. Now if we could just get newspaper insert advertisers to do the same . . . .
• When trying to analyze what triggered an allergic reaction keep
in mind that many reactions are “biphasic.” That is, after exposure to an
airborne allergen or a food, many people have not only an immediate
reaction, but also a second, delayed reaction (delayed up to 8 to 12
hours) after a single exposure.
• This is ragweed season. Keep in mind that rainfall releases more
ragweed pollen from the plants. Certain foods augment ragweed allergy,
especially melons and chamomile.
Now, say that fast three times with your mouth full of mushrooms. Shitake toxicoderma is a very common dermatitis in Asia, especially, China, Japan and Korea. However, it is being seen more commonly in the U.S. as the popularity of shitake mushrooms increases. The rash is fairly unique, consisting of a long linear array of urticaria. The skin looks like it has been whipped with cat-o-nine tails having red raised streaks that are very pruritic. The itchy lines can last for several weeks, and typically occur within a day of eating raw or cooked shitake mushrooms.
The mechanism of rash is felt to be due to Lentinam a polysaccharide found in the mushrooms that has immune-modulating effects. In fact, Lentinan has been used for chemotherapy in the treatment of colon and gastric cancers, It seems that individuals who get the rash have a hyper-immune response. Sun exposure can act as an adjunctive factor. The rash can be treated with steroids, usually topically, but if the problem is severe, oral steroids are used.
Since the article in the last issue of Allergic Reaction about Ramsay Hunt Syndrome from shingles, four patients from this office have commented on the much more common problem from shingles. That is eye involvement. Four individuals either had the complication themselves or knew a relative or friend with the eye involvement. All four of them felt that since the eye issue is so severe, people should know about it so they can protect themselves with the vaccine.
So here are some facts:
The most common complication of shingles (herpes zoster) is post-herpetic neuralgia. This occurs in about 20 percent of people who have shingles and can be a life-long source of recurrent pain in the area where the shingles broke out.
The second most common complication of shingles is herpes zoster opthalmicus (eye involvement), which occurs in about 2.5 to 3 percent of cases of shingles. Types of eye problems include conjunctivitis, iritis, uveitis and keratitis. All of these conditions can lead to varying degrees of loss of vision – including blindness. In some people the eye condition re-occurs repeatedly, even though the shingles don’t.
Once again, the best prevention for this complication is vaccination. Of note, when the vaccine was first released, the recommended age was 60 and older. Because the vaccine has proven to be so safe and so effective in preventing shingles and its complications, the age recommendation has been shifted to 50 and older.
The frequent rains this summer have led to a bumper crop of hungry mosquitoes. Although many repellants are available, the most effective compound seems to be DEET. It works because its scent is extremely irritating to biting insects, such as mosquitoes and fleas. Unfortunately, DEET is fairly allergenic with upwards of 30 percent of individuals developing a rash after repeated use. The types of rash seen are contact dermatitis (looks like poison ivy), eczema and urticaria (hives). The fact that DEET is a somewhat irritating chemical, and that it is repeatedly applied to the same skin areas, leads to the development of allergy.
Luckily, a new effective repellant has recently been developed – picordin. It, too, works because its scent dissuades biting insects; however, unlike DEET, it is not irritating or allergenic to the skin. Also, it is tolerated even in individuals already allergic to DEET.