Currently eight different human herpes virus are recognised, which are divided into three subfamilies. The cause of cold sores is usually Type 1 (HSV-1), more rare but increasingly more common as well is HSV-2, which was for a long time exclusively considered to be the causal pathogen of genital herpes. Antibodies against HSV-1 in Germany occur in about 88 percent of adults. Recurring herpes infections occur with 20 to 40 percent of those affected, as a result of reactivation of the virus. The herpes virus is totally dependent: if the host is infected once, the virus remains, in spite of the antibodies created, in a latent state in the nerve cells for life. There is one consolation: after age 35, these recurrences are generally more rare.
This type of phase again
If an itching, pain or burning is noticed, it is usually then too late. The infection goes through seven phases:
- Prodromal phase: pain, tingling, burning, tightness with still intact skin. This does not occur in all patients.
- Erythema phase: The skin reddens.
- Papular phase: Painful papules appear.
- Vesicular phase: papules “blow” out to become liquid-filled vesicles. The secretion contains millions of virus particles and is highly infectious upon contact.
- Ulceration phase: breaking and fusing of the vesicle formation into painful, oozing wounds.
- Encrusting phase: formation of strongly itching crusts and scabs.
- Healing phase: residual healing of remaining redness and swelling without scar formation.
Depending on the literature source these phases are sometimes instead summarised in five phases. Matters are serious if the initial pathogen infection migrates upward and triggers herpetic meningal encephalitis.
Stress makes small swellings break out
Feelings of disgust, cold, fever, UV-radiation, menstruation: triggers for cold sores are varied. Particularly important triggers however are stress and exhaustion, as is documented impressively in recent studies as well. In a French study it was found that for up to 60 percent of the 2056 patients these two factors acted as triggers for their herpes recurrences. Stress-plagued people have twice as much chance of getting cold sores as relaxed people. The stress hormones adrenalin and noradrenalin and cortisol increase the viral replication rate. In addition, the stress transmitters hinder activation of macrophages by interferons and the migration of natural killer cells. Thus specific recognition and destruction of virus-infected cells via cytotoxins and apoptosis is reduced.
In one pilot study psychologists Pfitzer and Clark from the University of Tübingen investigated the effectiveness of hypnosis therapy on recurrent cold sore infections. After five sessions of therapy herpes ocurred significantly less frequently and less intense than in the control group. Presumably the reason for the success is the stress reduction gained through the hypnosis.
Leaves, oils, roots as virus killer
In non-specialist press, dozens of home remedies are in circulation. A homemade garlic paste is even recommended. Whether it’s the disinfectant sulphur compounds or the kiss-repelling properties which bring this success is not mentioned. Toothpaste is also questionable. It does bring about drying and can act as a mild disinfectant, but a virustatic effect is certainly not discernable. The crusts can indeed come off earlier, but the colonisation process by other germs can be favoured by this.
Lemon balm leaf extract
In the case of antiviral screening using plant extracts, over a thousand plants with antiviral properties have been identified. Phenolic compounds such as saponins, anthranoids such as hypericin and aloeemodin, flavonoids such as quercetin, phenol carboxylic acids such as rosmarinic acid, and tannins are only a small selection. In another randomised study by Koytchev, Alken and Dundarov 66 patients who experience at least four episodes of herpes each year were treated with a cream containing lemon balm leaf extract (Lomaherpan ®). The subjects had to apply cream for five days four times a day. The authors verify that the preparation possesses significant efficacy. Further studies by Wölbling et al. showed that the lemon balm cream shortens the healing period of the herpes episode and significantly prolongs the recurrence-free intervals.
Tea Tree Oil
In one randomised, placebo-controlled study of 20 herpes infected patients, the effect of tea tree oil was investigated. In the verum group, a 6% strength tea tree oil gel was used, the rest received a placebo preparation. The period until the occurrence of re-epithelisation for the oil group was nine days and for the placebo group 12.5 days. Because of the small number of patients, it can certainly not be said to be of significance. It is also questionable whether the study can carry the label ‘placebo-controlled’. Tea tree oil is so pungent that the placebo gel can certainly be immediately identified. What’s more the relatively high risk of allergy to tea tree oil certainly does not make it a herpes hit.
Rhubarb and sage versus acyclovir
In a randomised comparative substance study by Büechi 145 patients with cold sores were tested for the effect of acyclovir; rhubarb-sage extract and sage extract (Phytovir ®) were tested. Another study involving rhubarb extract versus virustatic antiviral was discontinued due to the insufficient effect of the phytopharmaceutical. The study began with a screening at the virology institute of the University of Zurich. Here sage leaves and rhubarb root showed an antiviral effect against HSV-1. Rhubarb combined with anthranoids and tannins was more potent than sage leaves with essential oil and tannins. The combination of rhubarb and sage (each 23 mg extract/g) showed themselves as effective in the study than acyclovir cream.
The average times to crust formation and to healing do not differ significantly among the three groups. The healing time for sage cream averaged 7.6 days, for the rhubarb-sage cream 6.7 days and for acyclovircream 6.5 days. The patients in the acyclovir-group showed less swelling, in the second follow-up visit the rhubarb-sage sage subjects presented with less pain compared with subjects using sage. In the comparison acyclovir versus rhubarb-sage no significant difference was shown. From treatment of AIDS patients it is known that the combination of differing substances is stronger than a monotherapy.
The standard of care as recommended in the ABDA guide on self-medication are the nucleoside analogues acyclovir and penciclovir, both available over the counter. They inhibit viral DNA polymerase and replication of herpes virions. Both pharmaceuticals also therefore act when the virus has already penetrated the cell. The duration of illness is shortened by about one to two days and the crusting process accelerates. The ointments are applied every two to four hours with a cotton swab. The patient should be advised to wash thoroughly afterwards so as to prevent virus spreading.
After 10 years of stagnation in the virustatic herpes killer market, in 2008 the long-chain saturated alcohol docosanol was permitted for use. It is permitted for therapy treament of cold sores during stage 1 and 2. In the assumed mechanism involved docosanol inhibits fusion between lipid-enveloped viruses and the plasma membranes and thus prevents its intracellular uptake and replication. In a joint analysis of both trials, the median time until healing with docosanol was 4.1 days compared with 4.8 days for the placebo (difference 17.5 hours). The same applies to the accompanying symptoms such as pain, tingling, or burning, which subside about half a day sooner, according to the result of a study by SACKS, S.L. et al. .
Das Arzneitelegramm (at 2008; 39: 58-9) sees major flaws in the study design and give it a negative rating: statistically speaking a difference in comparison with placebo only shows up in one of the two individual studies. Three additional unpublished negative studies cast doubt that even the meager benefits documented could be just a statistical accident. We do not recommend docosanol. The ointment pyrophosphate foscarnet sodium, also approved as a lotion, is available by prescription. It is also sometimes used on cold sores off-label. In an earlier placebo-controlled comparison by Lawee et al. involving 143 patients, a 3% preparation had no detectable effect on healing time.
Zinc orally as prophylaxis
Zinc salts such as zinc sulphate or zinc histidine inhibit the penetration of the virus into the host cells via dissociated zinc. They also promote wound healing through drying out of blisters. This effect is not to be confused with that of zinc ointment or paste. In these galenic preparations the zinc salt is indeed present at high concentrations, but as inorganic oxide. This creates physical dehydration, but does not dissociate, and therefore has no virustatic properties. In a study by Femiano et al. the influence of zinc sulphate on the incidence of disease, administered at 2 x 22.5 mg zinc per day, was investgated. Patients included were those who had more than 6 herpes attacks per year. The subjects received zinc treatment twice a year for two months. After one year the number of attacks was 3 fewer, the disease duration per episode was also reduced. In other studies zinc gluconate and zinc lactate proved equally effective against HSV 1 and 2
One orthomolecular approach involves oral therapy using lysine. This amino acid behaves as an antagonist of arginine, a substance which promotes growth of herpes virus. Lysine replaced arginine in the common transport system through the intestinal wall. The virus wrongly builds lysine into its DNA structures, bringing its growth to a stop. In a study by Griffith, Norin and Kagan, the effect of 312-1200 mg of lysine as a prophylactic against cold sores was investigated. The episode frequency and duration time shortened.
Also approved as a medical device is the agentless cold sore plaster. This covers the blister according to the principle of moist wound healing via occlusion. Cold sore also stress the patient mentally, which in turn promotes a new infection. A concealing cosmetic effect could theoretically at least counteract a new episode.