From the Guidelines
The recommended dose of L-lysine for managing herpes simplex virus infections is typically 1,000-3,000 mg daily, divided into multiple doses. For acute outbreaks, taking 3,000 mg daily (often as 1,000 mg three times daily) may help reduce symptom severity and duration. For maintenance and prevention, 1,000-1,500 mg daily is commonly used. L-lysine should be taken between meals on an empty stomach for better absorption, with water. This amino acid supplement works by competing with arginine, another amino acid that the herpes virus needs for replication. By maintaining higher lysine-to-arginine ratios in the body, viral replication may be inhibited. While using L-lysine, it's advisable to reduce consumption of arginine-rich foods like nuts, chocolate, and certain seeds. L-lysine supplementation should be accompanied by adequate hydration and can be used alongside prescribed antiviral medications, such as acyclovir or valacyclovir, as recommended by guidelines 1. Those with kidney or liver conditions should consult a healthcare provider before starting supplementation. It's also important to note that daily anti-HSV suppressive therapy, such as with acyclovir, valacyclovir, or famciclovir, can be effective in preventing recurrences, especially for persons who have frequent or severe recurrences 1.
From the Research
L-Lysine Dosage for Herpes Simplex Virus Infections
The recommended dose of L-lysine for managing herpes simplex virus infections varies across studies.
- A study from 1978 2 found that doses of 312-1,200 mg of lysine daily were effective in accelerating recovery from herpes simplex infection and suppressing recurrence.
- A 1987 study 3 used a dose of 1,000 mg L-lysine per dose, three times a day for 6 months, and found that L-lysine treatment reduced the occurrence, severity, and healing time of recurrent HSV infection.
- A review of the evidence in 2017 4 suggested that doses of less than 1 g/d may be ineffective for prophylaxis or treatment of herpes simplex lesions, while doses in excess of 3 g/d may improve patients' subjective experience of the disease.
Efficacy of L-Lysine
The efficacy of L-lysine in managing herpes simplex virus infections is also a topic of debate.
- Some studies, such as the 1978 study 2 and the 1987 study 3, found that L-lysine was effective in reducing the occurrence, severity, and healing time of recurrent HSV infection.
- However, other studies, such as the 1984 study 5, found that L-lysine was not effective in treating or preventing recurrent herpes simplex infection.
- The 2017 review 4 suggested that L-lysine supplementation may be ineffective for prophylaxis or treatment of herpes simplex lesions without a low-arginine diet, and that longer duration controlled studies are needed to definitively test its role in herpes simplex prophylaxis.
Safety and Precautions
Patients with cardiovascular or gallbladder disease should be cautioned and warned of the theoretical risks of lysine supplementation 4.
- There is limited information available on the safety and efficacy of L-lysine in immunocompromised patients, who may require alternative treatment regimens, such as those described in the 2003 study 6.