Influenza

Hormones That Enhance Immune Response

DHEA is an adrenal hormone with immune system–boosting effects that seems to protect against a variety of infections, including influenza, in animal models. It works by enhancing cytokine secretion. DHEA enhances the immune response and helps combat bacterial and viral infections, including influenza (Padgett DA et al 1997; Padgett DA et al 2000). The age-associated decline in its concentration correlates with a decline in immunity. DHEA supplementation has been shown to reverse the age-related decline in immunity and protect aged mice against influenza (Danenberg HD et al 1995).

Administering 50 mg of DHEA a day to elderly men resulted in the following immune enhancements compared to placebo (Khorram O et al 1997):

• An increase of 35 percent in the number of monocyte immune cells
• An increase of 29 percent in the number of immune B-cells
• An increase of 62 percent in B-cell activity
• An increase of 40 percent in T-cell activity (total number of T-cells not affected)
• An increase of 50 percent in IL-2
• An increase of 22 to 37 percent in the number of natural killer cells and an increase of 45 percent in natural killer cell activity

One reason that influenza can be so lethal to aging people is that their immune systems are weak. A deficiency in DHEA appears to be partially responsible for the age-related decline in immune function (Fulop T Jr et al 1999; Khorram O et al 1997). One study showed that a metabolite of DHEA augmented activation of T-helper cells and protected mice from a lethal influenza virus infection (Padgett DA et al 1997).

Melatonin is a hormone secreted by the pineal gland that enhances the production of key components of the immune system, such as natural killer cells and several cytokines, including IL-1, IL-6, and IL-12, and interferons (Lissoni P et al 1994c; Lissoni P et al 1994a; Lissoni P et al 1994b; Lissoni P et al 1989; Maestroni GJ 1993; Maestroni GJ 1999). Melatonin is an antioxidant that amplifies IL-2's antiviral and anticancer effects.

The conclusion of one melatonin review article was: “The immunomodulatory, antioxidant, and neuroprotective effects of melatonin suggest that this indole must be considered as an additional therapeutic alternative to fight viral diseases.” (Maestroni GJ 1999).

Another study examined the immune function benefits of melatonin and found that melatonin activated IL-2 and gamma interferon, the body’s natural hormonelike agents that facilitate T-helper cell production (Bonilla E et al 2004).

Taking higher-than-usual doses (200 to 400 mg) of DHEA in the morning and higher-than-usual doses (10 to 50 mg) of melatonin before bedtime would appear to be logical approaches to battling a viral infection.

Ribavirin

Ribavirin is a broad-spectrum antiviral drug that was first synthesized in 1972 (Snell NJ 2001). It was approved in the United States in the late 1990s to treat the hepatitis C virus, and it is used in other countries to treatment influenza (Cianci C et al 1998). Ribavirin has been proved to be effective at limiting the duration and severity of viral illness. In France, ribavirin, administered by nebulizer, is successfully used to treat severe cases of influenza (Leophonte P 2005). Ribavirin works by inhibiting the replication of the virus’s DNA (Magden J et al 2005).

In a recent study, mice infected with influenza were given ribavirin at a dose between 18 and 37.5 milligrams per kilogram per day (mg/kg/day). The drug was shown to be highly effective in preventing death and reducing the presence of virus in the lungs (Sidwell RW et al 2005). Another study found that ribavirin was 90 to 100 percent effective at preventing death in mice infected with influenza B. The mice were simultaneously given a drug that boosted viral replication to enhance the lethality of the flu strain. Even when treatment with ribavirin was started 4 days after infection, ribavirin still produced a 40-percent survival rate (Smee DF et al 2004).

Other studies have also shown positive results. In one case study, three patients who had severe lower respiratory tract influenza or parainfluenza were treated with a continuous intravenous ribavirin infusion, at 5 mg/kg/hour for the first 8 hours, followed by 1.5 mg/kg/hour for 2 to 6 days. Researchers found the rate of viral shedding (a measure of viral activity) was diminished in one patient and ceased completely in the other two (Hayden FG et al 1996).

Some reports have linked the use of ribavirin to mild anemia. The Vitamin Depot Online.com Foundation believes this anemia is linked to drug-related free radical damage that affects red blood cells. Take adequate antioxidants to provide protection against anemia if you take ribavirin for the flu. We recommend taking antioxidants during influenza infection even without ribavirin.