Chemical structure of azithromycin.
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Azithromycin is the first macrolide antibiotic belonging to the azalide group. Azithromycin is derived from erythromycin by adding a nitrogen atom into the lactone ring of erythromycin A, thus making the lactone ring 15-membered. Azithromycin is sold under the brand names Zithromax and Sumamed, and is one of the world's best-selling antibiotics. Azithromycin is used for the treatment of respiratory-tract, soft-tissue and genitourinary infections. more...

Zoledronic acid


Azithromycin's name is derived from the azane-substituent and erythromycin. Its accurate chemical name is

(2R,3S,4R,5R,8R,10R,11R,12S,13S,14R)-13- -2-ethyl- 3,4,10-trihydroxy-3,5,6,8,10,12,14-heptamethyl -11--1-oxa- 6-azacyclopentadecan-15-one.


A team of Pliva's researchers, Gabrijela Kobrehel, Gorjana Radobolja-Lazarevski and Zrinka Tamburasev led by Dr Slobodan Dokic, discovered azithromycin in 1980. It was patented in 1981, and was later found by Pfizer's scientists while going through patent documents. In 1986 Pliva and Pfizer signed a licensing agreement which gave Pfizer exclusive rights for the sale of azithromycin in Western Europe and the United States. Pliva brought their azithromycin on the market in Central and Eastern Europe under the brand name of Sumamed in 1988, and Pfizer Zithromax in 1991.

Available forms

Azithromycin is commonly administered in tablet or oral suspension. It is also available for intravenous injection.

Mechanism of action

Azithromycin prevents bacteria from growing by interfering with their protein synthesis. Azithromycin binds to the 50S subunit of the bacterial ribosome, and thus inhibits translation of mRNA. Azithromycin has similar antimicrobial spectrum as erythromycin, but is more effective against certain gram-negative bacteria, particularly Hemophilus influenzae.


Unlike erythromycin, azithromycin is acid-stable and can therefore be taken orally without being protected from gastric acids. It is readily absorbed, and diffused into most tissues and phagocytes. Due to the high concentration in phagocytes, azithromycin is actively transported to the site of infection. During active phagocytosis, large concentrations of azithromycin are released. The concentration of azithromycin in the tissues can be over 50 times higher than in plasma. This is due to ion trapping and the high lipid solubility.


Azithromycin's half-life is approximately 2 days, and it's fairly resistant to metabolic inactivation. Its main elimination route is through excretion in the biliary fluid, and some can also be eliminated through urinary excretion. Azithromycin is excreted through both of these elimination routes mainly in unchanged form.

Side effects

Most common side effects are gastrointestinal; diarrhea, nausea, abdominal pain and vomiting.


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Treating infections without antibiotics
From Townsend Letter for Doctors and Patients, 11/1/05 by Jacob Teitelbaum

Many people do not realize how many things they can do before resorting to using an antibiotic to clear an infection. If your patient is coming down with a respiratory infection such as a cold or the flu, I recommend that you try the following:


* Give natural thymic hormone. This is available as a product called ProBoost from Klabin Marketing: 800-933-9440), and is a very effective immune stimulant. Dissolve the contents of one packet under your tongue three times a day and let it absorb there (any that is swallowed is destroyed). A study in CFS patients with markedly elevated Epstein-Barr antibody levels showed a dramatic drop in the antibody levels after six weeks of treatment with thymic hormone. Many physicians are finding that thymic hormone has been very helpful for CFS/FMS and other patients with acute or persistent viral, yeast, bowel, or other infections. I have found that using it for two or three days at the onset of an infection can shorten the length of the infection dramatically, and often stops it on the first day.

* Take 1,000 to 8,000 milligrams of vitamin C a day--enough to get diarrhea, then cut back to comfortable level.

* Suck on a zinc lozenge five to eight times a day. Make sure that the lozenges have at least 10 to 20 milligrams of zinc per lozenge. Less than this will not be effective. Zinc lozenges have been known to speed the time it takes to recover from a cold by about 40%. General Nutrition Centers sells a very good one.

* Drink plenty of water and hot caffeine-free tea (or hot water with lemon) and rest!

* Take Oscillococcinum, a homeopathic remedy available at most health food stores and some supermarkets, for flu-like symptoms such as chills, fever, achiness and/or malaise. It speeds healing and eases discomfort. It is best taken early in the infection--as soon as the patient has any Flu-like symptoms.

* For sinus infections, try nasal rinses. Dissolve 1/2 teaspoon of salt in a cup of lukewarm water. Inhale some of the solution about one inch up into your nose, one nostril at a time. Do this either by using a baby nose bulb or an eyedropper while lying down, or by sniffing the solution out of the palm of your hand while standing by a sink. Then gently blow your nose, being careful not to hurt your ears. Repeat the same process with the other nostril. Continue to repeat with each nostril until the nose is clear. Rinse your nasal passages at least twice a day until the infection improves. Each rinsing will wash away about 90% of the infection and make it much easier for your body to heal.

* 1,000 milligrams of olive leaf extract three times a day for three to seven days. Although probably not as effective as thymic hormone, olive leaf extract seems to be helpful against viral respiratory infections and, perhaps, yeast infections. It seems most helpful in fighting the common cold. In my experience, it has been very helpful for about half the people who try it--the cold is gone in twenty-four to thirty-six hours. If it causes nausea, cut the dose in half.

* Take acetaminophen (in Tylenol and many other over-the-counter pain relievers) for muscle aches and use Cepacol or Chloraseptic mouthwash as a gargle for a sore throat. Gargling with salt water, mixed as described above for the nasal rinse, also helps a sore throat. If you use acetaminophen frequently, you should also take 500 milligrams of supplemental N-acetylcysteine (NAC) each day so you don't deplete your glutathione levels.

* Try using a humidifier or vaporizer in your bedroom. You can also make a steam room by running a hot shower in your bathroom and then breathing in the steam. Or try using a steam inhaler, such as the one available from Bernhard Industries. This is also wonderful for chronic and acute sinusitis.

* Take at least 500 milligrams of vitamin C a day for prevention.

If, despite these measures, nasal and lung mucus is yellow after seven to fourteen days, or if you are feeling worse after three to four days, you may have to consider taking a course of antibiotics. If you do, you should take nystatin while on the antibiotic. Erythromycin antibiotics such as azithromycin (Zithromax) and clarithromycin (Biaxin) are usually preferable to penicillin antibiotics. Interestingly, my patients have sometimes found that all their CFIDS symptoms (not just the cold) improve while they are taking an erythromycin or tetracycline antibiotic. If that happens, I recommend a twelve-week course of 500 milligrams of Biaxin or 100 milligrams of doxycycline twice a day. If you feel better on the antibiotic (take thymic hormone, echinacea, and the antifungal nystatin in con-junction with it), keep repeating six-week courses until the symptoms stay gone. I would also check for Lyme disease using a blood or urine test. And for most of my patients who repeatedly get respiratory infections that take forever to go away, I consider an empiric trial of prescription hydrocortisone (Cortef) at a dosage of 7-1/2 milligrams in the morning and 5 milligrams at noon for two to three months.

As a preventive for respiratory infections, the flu vaccine is a double-edged sword for people with CFIDS/FMS. In some CFIDS/FMS patients, it can cause mild flulike symptoms for a few days. In rare cases, it can cause a severe flare-up of symptoms. Still, unless you are one of the 10% of CFIDS/FMS patients who feel worse after the flu shot or other vaccinations, I would get a flu shot. For most people, the benefit can significantly outweigh the risk. Interestingly, a recent Scandinavian study showed that having frequent vaccinations against Staphylococcus bacteria significantly improved symptoms in fibromyalgia patients. The researchers felt that it helped by stimulating the immune system.

Taking at least 500 milligrams of vitamin C a day is also a very good idea. And dress warmly. A cold breeze blowing across a patient's muscles can make fibromyalgia symptoms flare up.

Jacob Teitelbaum, MD is director of the Annapolis Research Center for Effective CFS/Fibromyalgia Therapies, which sees patients with CFS/FMS from all over the world (410-573-5389; and author of the best selling book "From Fatigued to Fantastic!" and "Three Steps To Happiness! Healing Through Joy." His newest book "Pain Free 1-2-3!" has just been released. CD sets of his workshops on effective CFS/Fibromyalgia therapies and pain management for both prescribing and non-prescribing practitioners are available at He accepts no money from any company whose products he recommends and 100% of his royalties for products he makes is donated to charity.

by Jacob Teitelbaum, MD

410-573-5389 *

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