Here is some information from Erica Verrillo's
CFS Treatment Guide v2:
WEATHER SENSITIVITY
The expression “feeling under the weather” has a literal meaning for people with CFS/ME, especially for those who suffer from concomitant fibromyalgia (FM).
In fact, so strong is the association between weather changes and exacerbation of pain in FM that weather sensitivity was included as one of its defining characteristics in Dr. Yunus's pioneering work on FM in the 1980s. There are a number of reasons why changes in weather can affect joints and skeletal muscles. Decreases in barometric pressure allow the small fluid-filled sacs surrounding joints to expand, irritating and inflaming the tissue around them. Fluid expansion leads to increased sinus problems, toothaches, and even migraines. In a 1990 study by D. Guedj and A. Weinberger, two Israeli scientists, 83% of arthritis sufferers and 77% of FM patients could successfully predict rain based on increased joint pain.
It is common knowledge among people with CFS/ME that weather changes produce not just pain, but a general worsening of symptoms. CFS sufferers in the same geographic area often exchange sympathetic phone calls just before storms, during impending pressure fronts, and on windy days (which signal a drop in barometric pressure). In situations where more than one member of a family is ill, the response to weather may be particularly dramatic because all ill members experience an exacerbation of symptoms simultaneously.
Fully one-third of the general population may be sensitive to weather changes, according to studies performed at Hebrew University in Jerusalem. Those who are weather sensitive commonly experience symptoms such as muscle pain, aching joints, insomnia, irritability, and the "blahs" as much as a day or two before the weather changes. The worst weather for the sensitive individual is characterized by a falling barometer and high humidity. The reasons for the mysterious clairvoyance of those who seem to know when the weather is going to change may have to do with neurochemical changes stimulated by radio waves sent out by advancing fronts.
Studies directed by Dr. Felix Sulman, head of the Bioclimatology Unit at Hebrew University, demonstrated that people who reported sensitivity to weather changes had unusually high amounts of serotonin and histamine in their urine a day or two before a weather change. Histamine is an inflammatory agent released during allergic reactions. Serotonin, a neurotransmitter and vasoconstrictor, is also an irritant and can be released in the body during emotional stress. According to Dr. Sulman, excessive amounts of serotonin, like histamine, can produce agitation, insomnia, irritability, runny or stuffy nose, inflammation of the eyeballs and lids, shortness of breath, sore throat, edema in hands and feet, migraine headache, nausea, dizziness, palpitations, flushes accompanied by sweating or shivering, diarrhea, and the constant urge to urinate.
Dr. Sulman maintains that the "sferics," or radio waves, released as a consequence of the increased electrical activity preceding a front, produce positive ions that in turn act to stimulate the release of serotonin and histamine. He also speculates that weather sensitivity may be genetically adaptive because increased moodiness might have served as a warning to get back to shelter as quickly as possible. Animals may be subject to the same mechanisms. It has often been observed that their uncanny foreknowledge of coming storms leads them to seek shelter before the weather changes.
People who are weather sensitive may also react similarly to changes in temperature. Dr. Sulman's group found that, in addition to increased histamine levels, hot weather produced decreased excretion of adrenal hormones (e.g., cortisol) signaling adrenal exhaustion. With prolonged hot weather, the symptoms of adrenal exhaustion become evident: low blood pressure, fatigue, listlessness, depression, confusion, difficulty performing mental tasks, and hypoglycemia. In some individuals the period of exhaustion may be preceded by transient hyperarousal of the thyroid – particularly at the onset of hot, dry weather – causing overactivity, insomnia, irritability, restlessness, palpitations, sweating, and diarrhea. Cold weather can produce similar effects.
Dr. Sulman has noted that prolonged hot weather stimulates the hypothalamus, the brain structure which signals the pituitary to release hormones that activate the adrenal glands. The hypothalamus-pituitary-adrenal (HPA) axis abnormalities common in CFS/ME (as noted by Dr. Mark Demitrack and colleagues) may be responsible for unusually rapid depletion of adrenal hormones and ensuing malaise brought about by heat. Increased histamine levels also have profound implications for the substantial number of people with CFS/ME who may also experience oversensitivity to histamine itself (CFIDS Chronicle, Summer 1993). Dr. Sulman's findings also predict higher reactivity to weather changes in women, who produce far fewer adaptive stress hormones than men and more histamine and serotonin in response to weather stress.
Dr. Michael Persinger, a neuroscientist at Laurentian University in Ontario, Canada, concurs that weather sensitive people may experience numerous symptoms from approaching weather fronts. Dr. Persinger found that dropping temperature, increased barometric pressure, and increased humidity cause sympathetic nervous system arousal. This results in increased urination, migraines, peripheral circulatory problems, and joint stiffness. Influxes of warm air with falling barometric pressure and high humidity are associated with parasympathetic responses (water retention, glaucoma, menstrual swelling). According to Dr. Persinger, the effects of weather fronts both precede and follow their passage. Parasympathetic activity is noticeable five to six hours before the passage of a cold front, while sympathetic activity increases from three to five hours afterward. Dr. Persinger has observed that the autonomic effects of weather fronts may continue for as long as 16 to 30 hours after the fronts have passed.
Dr. Persinger's theory is that those with unstable hypothalamic function have exaggerated responses to weather fronts. For example, those with parasympathetic dominant autonomic function will be “pushed over the edge” by oncoming storms, resulting in lethargy, increased pain, orthostatic hypotension, and depression. Sympathetic dominant individuals would experience euphoria and insomnia. Like Dr. Sulman, Dr. Persinger notes that there is a predominance of women among the weather sensitive.
Many people with CFS/ME and FM note a definite worsening of symptoms, including anxiety, myalgia, headache, inflammation, and insomnia just before storms and the passing of weather fronts, particularly during conditions of low barometric pressure and high humidity. Many also note a worsening of symptoms during hot weather. We are not aware of anyone with CFS/ME who has been tested for serotonin, histamine, or adrenal hormone levels in the urine before a storm or during hot or cold weather, so it cannot be certain that altered hormone levels cause the weather sensitivity experienced by people with CFS/ME. However, many of Dr. Sulman's findings support what is known about hormonal irregularities caused by CFS/ME, as do those of Dr. Persinger.
Some people, paradoxically, may actually feel better before a storm. It is possibly that increased serotonin levels—or, more likely, the constriction of blood vessels (leading to a rise in blood pressure) due to changes in barometric pressure—may contribute to increased energy. Some CFS/ME patients report that they can tell a storm is coming if they feel an urge to clean off their desks, do taxes, or pay bills that have been accumulating. This may, in fact, be the only benefit of weather sensitivity, so these individuals should make hay while the sun shines – or doesn't, in this case.
TREATMENT TIPS
To minimize the effects of impending storms, Dr. Sulman recommends avoiding sources of positive ionization (forced-air heating and cooling, friction between synthetic fabrics, and air pollution) as much as possible. Exposure to negative ions is also helpful. Ionizing machines can be purchased to increase negative ion ratios in your bedroom. However, make sure to read product descriptions carefully. Dust-removing ionizers, because they produce ozone and nitrous oxide, may, in fact, worsen health problems. If you are interested in purchasing a negative-ion ionizer, look for an ozone-free product. (These generally run about $125.)
Some essential oils reputed to increase the effectiveness of negative ions are cypress, lemon, orange, bergamot, pine, bois de rose, cedarwood, grapefruit, pettigraine, patchouli, and sandalwood. For people with SAD (seasonal affective disorder), full-spectrum lightbulbs and light boxes can be purchased.For people sensitive to humidity, it may be worthwhile to purchase a dehumidifier for the bedroom. Air-conditioning systems also reduce the amount of humidity inside the house. Although Dr. Sulman cautions against forced-air cooling, sometimes the relief brought by the decrease in humidity offsets any negative effects of the machinery. For all types of weather sensitivity, it is important to be aware of impending storms and fronts. Listen to weather forecasts and keep a log of symptoms before weather changes to see which ones produce the most severe effects. Plan to take it easy on those days.