Thursday, November 21, 2013

The End of Ozone-Depleting Inhalers

Since 2009, a quiet transition has been occurring to replace the propellant currently being used in inhaled medications with a more environmentally friendly product. By the end of this year, the last two medications that use an ozone-depleting propellant will have been removed from the market.

Prior to 2009, chloroflurocarbons (CFCs) were widely used to propel inhaled medications from a canister into the patient's lungs. While this chemical propellant was safe to the patient, it was found to have damaging effects on the earth's ozone layer. Loss of the ozone layer allows more of the sun's harmful ultraviolet (UV) radiation to reach the earth. Excessive UV radiation can lead to an increased incidence of skin cancers and the development of cataracts.
                                                                                   
It may seem implausible that the relatively small amount of propellant in a small canister could cause problems of that magnitude, but when you realize that over 52 million prescriptions are written for a single inhaled medication each year, the cumulative amount of CFCs being released into the atmosphere was significant.

Inhaled medications are used primarily to treat lung diseases, such as asthma and chronic obstructive lung disease (emphysema). Some of the more common types of inhaled medications include:
  • Corticosteroids---(Pulmicort, Flovent, Azmcort, others) These help reduce airway inflammation and tightening of the bronchial tubes.
     
  • Bronchodilators---(Albuterol, Proventil, Ventolin, others) Bronchodilators are used to relax small muscles in the airways, allowing air to flow more easily in and out of the lungs.
     
  • Non-steroid anti-inflammatory medications (Intal, Tilade) These inhaled anti-inflammatory medications are used most often to prevent an asthma attack from occurring.
The discontinuation of CFC-propelled inhalers came about as a result of the US Clean Air Act and an international treaty known as the Montreal Protocol on Substances That Deplete the Ozone Layer. The chemical propellants that are replacing CFCs are ozone-friendly chemicals known as HFAs, hydrofluoroalkanes. A second approved method of delivering inhaled medications involves the use of dry powder inhalers. These are somewhat more difficult, however, to use than the metered dose inhaler (MDI) that uses a chemical propellant.

The change to HFA-propelled inhalers has been going on since 2009, in order to allow those people to make the switch more gradually. The last of the CFC-containing inhaler will be off the market by. Dec. 31, 2013. Testing has shown that there are minimal differences in the effectiveness of the two types of inhalers. The major differences have to do with the HFA inhalers being more expensive as well as requiring more maintenance to prevent clogging of the inhaler's nozzle.

Several of the replacements for those that contained CFCs will have the initials, HFA, at the end. For example, the brand name metered-dose inhalers that are replacing albuterol bronchodilatos are, Proventil-HFA, Ventolin-HFA, Xopenex-HFA, and ProAir-HFA. Symbicort, QVAR-HFA and Flovent-HFA are a few of the trade-named inhaled corticosteroids new to the market. As mentioned, some of the inhaled medications are available in powered form also. Pulmicort Turbohaler and Flovent Diskus are powdered forms of corticosteroids. Advair Diskus is a powdered combination of a bronchodilator and corticosteroid.

While there are definite drawbacks to these newer HFA-containing inhaled medications, in particular their expense, it is hoped that the "greater good" will be served in the long term by reducing the CFF-related damage to the ozone layer.

Monday, November 18, 2013

Seasonal Affective Disorder

Seasonal Affective Disorder (SAD) is a mood disturbance that characteristically occurs in the autumn or winter with remission in the spring and summer. Its development coincides with the fewer hours of sunlight available during the winter. In a given year, up to 5% of the U.S. population is thought to experience mood changes during the winter. In contrast with the more common "wintertime blues", however, SAD is characterized by more severe depressive symptoms.


How can lack of sunlight lead to depression? Even though the mechanism for the development of SAD is not completely understood, it is clear that light affects brain chemistry.
With varying amounts of sunlight, people experience a shift in their circadian rhythm or "internal clock" that regulates the 24-hour cycle of biological and mental processes. This alteration in circadian rhythm, along with changes in a sleep-related hormone known as melatonin and a brain chemical known as serotonin are thought to underlie the development of SAD.

How is SAD diagnosed? There are no blood tests to confirm the presence of SAD. The diagnosis is made based on the characteristic signs and symptoms that occur during predictable times of the year. Symptoms of SAD can include:
  • Fatigue or excessive sleeping
  • Depression (feelings of sadness, apathy, hopelessness, etc.)
  • Lack of interest in normal activities or in social interactions
  • Overeating and weight gain or sometimes weight loss
  • Decreased ability to concentrate
Is there anything that I can do to prevent SAD? Those who are susceptible to the effects of shorter days or who experience mild symptoms of SAD may be able to circumvent more severe symptoms by:
  • Increasing exposure to sunlight. Opening blinds and arranging the home or office to take advantage of sunlight during the day.
  • Getting regular exercise. This helps by relieving stress and improving sleep patterns. If nothing else, taking a walk during the sunny part of the day can be beneficial.
  • Socializing so that you stay connected with people you enjoy being around.
  • Although not always practical, taking a trip to a sunnier part of the world during the winter can help to reset one's internal clock to a more summer-like state.
Fortunately, in many cases, SAD symptoms resolve on their own when daylight hours lengthen, and remain symptom free throughout the spring and summer.

What can be done when SAD becomes more severe? In cases when lifestyle measures aren't adequate, light therapy (phototherapy) has proven to be an effective treatment option. Typically this involves exposure to a special florescent lamp for 30 minutes, up to a couple of hours each day. Phototherapy is thought to suppress the body's natural release of melatonin and help reset the "internal clock". With severe symptoms, antidepressant medications including paroxetine (Paxil), sertraline (Zoloft), and (Wellbutrin XL) may be beneficial.

What's new in SAD treatment? There is growing evidence that a type of "talk therapy" known as cognitive behavioral therapy (CBT) is also beneficial in treating SAD. CBT has been used in the treatment of major depression for years, but has only relatively recently begun to be used in the treatment of SAD. A primary goal of cognitive behavior therapy is to teach patients to take control of how they interpret and deal with self-defeating thoughts. The therapist may also encourage positive behaviors such as engaging in regular physical activity during the sunniest part of the day during the winter. A major benefit of CBT over other forms of treatment is that its effects appear to carry over into subsequent winter seasons.

Tuesday, November 12, 2013

White, Blue, and Red-Raynaud's and the Colors of the Flag

Raynaud's (ray-NODES) is a condition that affects blood vessels, primarily in the fingers and toes. It was named for Dr. Maurice Raynaud, a French physician who first described the condition in a young woman whose fingertips changed colors when she was cold or under stress. There are two primary types of Raynaud's. The first, known as Raynaud's Disease or Primary Raynaud's, is a relatively benign condition with no known underlying cause. The second, referred to as Raynaud's Syndrome or Secondary Raynaud's develops in conjunction with an underlying medical condition.

What happens during an episode? The manifestations of Primary Raynaud's usually develop as an exaggerated response to cold. While it is normal for blood vessels in the skin to constrict in order to maintain core temperature, in Raynaud's the blood vessels narrow to the point that blood flow is markedly restricted. This is usually noted in the fingers or toes, often with the classic color changes---white, blue, and red. First, the digits turn white as a result of restriction of blood flow. This may be followed by numbness, tingling, and a bluish discoloration of the skin. Once the circulation begins to return the affected digits turn red and throb prior to returning back to normal. Symptoms last until the skin is rewarmed, after which normal blood flow to the skin recovers in around 15 minutes.

 
Who gets Raynaud's? Raynaud's is thought to affect up to 10% of the population, with the great majority of these having Primary Raynaud's. Primary Raynaud's is more common in women than in men, usually developing before the age of 30. Although a definite genetic link for Primary Raynaud's has not been established, in many families, more than one member has the condition. Secondary Raynaud's usually begins after the age of 30 and often develops in conjunction with a connective tissue disease, such as scleroderma or lupus. It can also develop in people who have sustained injuries or frostbite to the hands and feet, smokers, and workers performing repetitive tasks or using vibrating tools.

How is Raynaud's diagnosed? There is no single blood test available to diagnose Raynaud's phenomenon. The characteristic color changes and precipitating factors often provide enough information for a doctor to make the diagnosis. Distinguishing the primary from the secondary form, however, may be more difficult. Questioning about possible secondary factors---injuries, occupational hazards, medications, etc.---may provide the underlying cause. In cases where connective tissue disease is suspected tests such as the antinuclear antibody (ANA) or erythrocyte sedimentation rate (ESR or "sed rate") may be performed.

How is Raynaud's treated? Primary Raynaud's has no cure. Fortunately, symptoms are typically mild and not associated with any blood vessel or tissue damage. When treatment is necessary, the following lifestyle measures help in most cases:
  • Take measures to avoid becoming cold in the first place. Wear a hat, mittens (rather than gloves), scarf, coat with snug cuffs, and warm socks and shoes during cold weather. Layer your clothing for extra warmth. If necessary, use commercial hand warmers or battery powered heated gloves.

  • Warm the body and the hands or feet at the first sign of an attack. If outside in cold weather, go indoors. Run warm water over your fingers or toes or soak in a hot tub.

  • When fingers are involved, swinging the arms in large circles helps to increase circulation.

  • Avoid smoking. The nicotine in cigarettes causes blood vessels to narrow, which may lead to an attack.

  • Avoid taking certain medications. Vasoconstrictors including beta-blockers (e.g. metoprolol, propranolol, others) and migraine headache medications in the triptan class (sumatriptan rizatriptan, zolmitriptan, eletriptan, others).can be responsible for triggering Raynaud's.

  • Control stress. If stress triggers attacks, try to remove yourself from the stressful environment. Relaxation techniques or biofeedback can also help decrease the number and severity of attacks.
Some people with Raynaud's, particularly those with a secondary cause, can develop serious complications, such as ulcerations on fingers or toes. In addition to lifestyle measures, these individuals may require treatment with medications. When medications are required, those that dilate blood vessels, such as calcium channel blockers (nifedipine, amlodipine, others) are considered to be the first line treatment. Another class of high blood pressure medications, alpha receptor blockers prazosin (Minipres) or doxazosin (Cardura) help in some cases.

What's on the horizon? Research is being conducted into more effective diagnostic measures, such as the use of laser contrast imaging, as well as new treatments to improve blood flow for those who have Raynaud's.