Conditions: Herpes Labialis Herpes Simplex Virus
Keywords: Glutamine Herpes Labialis Herpes Simplex Virus Cold Sore
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 11
Healthy volunteers: no

Brief summary:
Background:

* A cold sore is usually a blistering rash on or near the lips, caused by infection with herpes simplex virus. After the first infection, the virus goes into a dormant (inactive) state, but it can continue to cause cold sores.
* Most people with the herpes simplex virus have a few episodes of cold sores per year. However, some individuals may have many recurrent episodes that are uncomfortable and may cause embarrassment. Researchers are attempting to find treatments that can decrease the number of cold sore episodes for people who have six or more episodes per year.
* Glutamine is a molecule called an amino acid and is one of the components that make up proteins in the body. Clinical studies using glutamine have addressed the potential of glutamine to improve immune function and to heal damaged tissue or to help healing.

Objectives:

\- To find out if the dietary supplement glutamine can help individuals with frequently recurring (more than six episodes per year) cold sores.

Eligibility:

* Patients between 18 and 65 years of age who have a history of having six or more cold sore episodes per year, and have not received certain kinds of drug treatment for the cold sores within 1 month of beginning the study.
* Patients who have two or more episodes of cold sores caused by the herpes simplex virus will be eligible for treatment as part of this study.

Design:

* Initial clinical visit for a physical examination and medical history, at which blood samples will be drawn for testing.
* Eligible participants will undergo a 4-month screening period. Patients who develop sores during this period will visit the NIH to have the sore examined to determine if it is caused by the herpes virus. Patients who have two or more episodes of cold sores caused by the herpes simplex virus will be eligible for treatment.
* Patients who are eligible for treatment will provide an initial blood sample and will receive randomized doses of either glutamine or glycine (another amino acid), which must be taken on a regular schedule twice daily, mixed with either liquid or soft food. Patients who develop sores during this period will visit the NIH to have the sore examined to determine if it is caused by the herpes virus. Blood, urine, and saliva specimens will be collected each month during the treatment period. A 2-week washout period will occur between the 2 treatment periods when no doses of glutamine or glycine will be taken.
* Patients will then undergo a second 5-month treatment period with either glutamine or glycine (whichever was not given in the first part of the study), taken in the same manner as before. Patients who develop sores during this period will visit the NIH to have the sore examined to determine if it is caused by the herpes virus.
* After the second treatment, patients will remain in touch with researchers for 1 month to note any changes.

Detailed description:
Frequently recurrent herpes simplex virus type 1 (HSV-1) infection of the lips or perioral area, known as herpes labialis, or commonly as cold sores, can cause discomfort, pain, and embarrassment. Traditional antiviral therapies are moderately effective in suppressing these recurrences. Studies have shown that the amino acid glutamine can affect HSV-1 reactivation in vitro. Glutamine has been studied in various clinical situations and has been found to decrease morbidity in critically ill patients (reducing nosocomial infections), in patients receiving chemotherapy or undergoing bone marrow transplantation (reducing severity of stomatitis, reducing incidence of infection, shortening hospital stay), and in patients with short gut syndrome (decreasing requirement for parenteral nutrition). No significant adverse consequences of glutamine therapy have been reported in these patients. We will conduct a randomized, double-blind, control-comparison crossover trial comparing the efficacy of glutamine versus glycine (control) to suppress recurrences of herpes labialis in patients with frequent episodes (greater than or equal to 6 per year). Based on our in vitro and in vivo data, we hypothesize that oral glutamine will decrease the number of recurrences of herpes labialis during a 5-month treatment period in participants with frequently recurring herpes labialis compared with control.

Arms:

Interventions: intervention 1: Glutamine intervention 2: Glycine
Intervention descriptions: intervention 1: Subjects were randomized to take one of the study agents, 15 gm by mouth twice daily for 5 months. After a 2 week washout period, subjects began the other agent at 15 gm by mouth twice daily for 5 months. intervention 2: Subjects were randomized to take one of the study agents, 15 gm by mouth twice daily for 5 months. After a 2 week washout period, subjects began the other agent at 15 gm by mouth twice daily for 5 months.

Protocol document: