Dear Dr. K: I’ve lost my sense of smell. Could this be due to allergy?
The answer to your question is, yes, it could be, but it is unlikely. I say that because on your recent visit here your allergies were under excellent control and the only time I’ve seen anosmia (loss of sense of smell) from allergy is when it is severely out of control.
A complication of allergy that frequently causes anosmia is nasal polyposis. Treatments of the polyps via nasal sprays and/or surgery usually returns the sense of olfaction (smell).
The American Journal of Medicine had a recent review article titled, “Placebo: The Good, the Bad, and the Ugly.”
Placebo effect is defined as any improvement in discomfort or illness resulting from an intervention possessing no physical effect. Historically, the best research techniques always include a placebo control group and double-blinding — that is, neither the researchers nor the study patients know which group is which until the study is completed. Interestingly, surgery and physical manipulation of the body, such as physical therapy and chiropractic, have greater placebo benefit than oral medication.
Such properly conducted research has led to the realization that there also exists a “nocebo” effect, which is symptoms or illness resulting from expectations or fears of a bad effect. (Kind of like reading a list of possible adverse side effects from a medicine and thinking you are experiencing some of the symptoms.)
Both the placebo and nocebo effects can occur as a “take-away” from the benefit of a traditional therapy, or can stand alone from an inert therapy.
The nocebo effect also is why all drug trials demonstrate significant rates of undesirable side effects in the control group. These negative reactions are felt to come from the individuals’ innate pessimism or tendency toward depression.
A study outlining the use of weekly azithromycin for COPD patients with frequent exacerbations was published recently in the world’s leading general medical journal, Lancet. “Frequent” was defined as three or more episodes in a year of these episodes of sustained worsening of these patients’ conditions.
Several cogent reasons warrant attempting to prevent these exacerbations. First and foremost, they make the patient sick and can lead to hospitalization, and sometimes to death. Also, each exacerbation can worsen the overall degree of lung impairment, kind of a racheting down in lung function. The patients in the year-long Lancet study were treated with 500 mg. a day of azithromycin for the first three days of each week.
This particular drug was chosen because it has immunomodulatory properties. That is, it works not only as an antimicrobial, but also as an anti-inflammatory. It is concentrated 200 times in the white blood cells, which go to the bronchial tissues. It also has a long half-life of about 70 hours after a dose.
Patients in the trial had 58 percent fewer exacerbations. Additionally, this benefit lasted for more than six months after the drug was stopped.
Are you having trouble with recurrent viral infections? Perhaps it’s because you also have a worm (helminth) infection. Immunology research recently published in Science suggests that.
Parasitic worms are strong activators of T-helper cell 2, a lymphocyte that then produces cytokines that can help kill helminths, but that also turns off production of the cytokine interferon, which is a mainstay for fighting viruses. Helminths also reprogram the macrophages (“big eaters”), a type of white blood cell, so that they fight the worms, but totally ignore viruses.
This double whammy on the immune system’s ability to fight viruses can lead to reactivation of latent viruses such as herpes or shingles, but also to greater chance of catching new viruses.
This latter issue especially applies in third-world areas where worm infestation is common, and along with HIV and Ebola viruses.
Believe it or not, the greatest increase in anosmia is coming from texting! This stems from the dramatic increase in “rear-ender” automobile accidents due to texting while driving. The whiplash injury frequently seen in these mishaps causes disruption (tearing) of the olfactory nerve as these fibers pass through the cranial bone into the nasal chamber.
Other neurologic problems that can cause loss of smell include meningitis, benign and malignant brain tumors in the frontal lobe area, and cerebral artery aneurysms. Finally, loss of sense of smell can occur as an early sign of Parkinson’s disease.
Going back to the allergy question, a very common cause of anosmia is chronic use of nasal decongestants such as Afrin, Neo-Synephrine and four-way nasal sprays. These medicines work by constricting blood vessels in the nasal membranes, and when used for protracted periods can lead to vascular injury to the delicate olfactory nerves.
Infections are another common anosmia cause; simple colds often cause a decrease in the sense of smell. Some viral and bacterial infections, however, can cause a more severe and protracted effect on smell sensation via toxicity to the olfactory nerves.
Also, certain molecular deficiencies can cause the loss, most notably low serum zinc levels and low vitamin B12 levels.
Finally, certain volatile chemical agents can cause loss of smell through either low-grade, long-term exposure or through accidental high-dose toxic exposure.
If you have high blood pressure and a cough, the latter could be caused by your anti-hyper-tensive. The two most common culprits are Beta-blockers and ACE inhibitors.
A leading cause for AGE (acute gastroenteritis) here in Florida is accidently swallowing water from pools and water parks.
If you have a latex or rubber allergy you may also be buffeted by eating the cross-reactive foods: avocado, banana and chestnut.