Last updated: August 9, 2021

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Welcome to our big lysine test 2021. Here we present all the lysine products that we have tested in detail. We have compiled detailed background information and added a summary of customer reviews on the internet.

We would like to make your purchase decision easier and help you find the best lysine product for you.

You will also find answers to frequently asked questions in our guide. If available, we also offer interesting test videos. Furthermore, you will also find some important information on this page that you should definitely pay attention to if you want to buy lysine.



  • Lysine is a vital amino acid that is involved in many important processes in the human body (but also in animals).
  • Lysine is found in many different animal and plant foods, although it is only found in small quantities in plant products, which is why vegetarians and especially vegans have to resort to lysine preparations.
  • The amino acid lysine is indispensable, which is why its regular consumption in adequate amounts is of high importance.

The Best Lysine in the United Kingdom: Our Choices

Guide: Questions you should ask yourself before you start taking lysine supplementation

What is lysine?

Lysine (also called L-lysine) is one of the most important amino acids (building blocks for proteins, which are mainly used to build body tissue), which is essential.

This means that the human body cannot produce this amino acid on its own and therefore it must be taken in through food.

Amino acids are chemical compounds with an amino group and a carboxylic acid group. They are necessary for building proteins and thus also for building body tissue. (Image source: / OpenClipart-Vectors)

Why do I need lysine and what exactly does it do?

Lysine is involved in many different and important processes in your body, which is why you should definitely take it regularly.

In addition, lysine is one of the most important ingredients in nutrient solutions for artificial nutrition.

After ingestion, lysine is absorbed through the mouth via special transport substances into the blood and distributed in the body, where it can then act in the respective areas.

Here you can find a list of the processes in which the amino acid lysine is involved and what it does:

  • Synthesis of proteins and other amino acids
  • Building muscles
  • Transport of other substances
  • Wound healing
  • Bone growth/strengthening of bones
  • Cell division
  • Collagen formation
  • Building up connective tissue
  • Promotion of enzyme activity
  • Strengthening the immune system
  • Reduction of arginine (amino acid)
  • protects against stress

As you can see, lysine is an indispensable building block in our organism and, due to its growth-promoting effect, is especially important for babies, children and adolescents.

What side effects can occur?

In general, no serious side effects should occur if the dosage is appropriate.

A long-term intake of about 3,000 mg of lysine daily should be harmless for adults. However, if too much lysine is consumed on a regular basis, the following side effects can occur:

  • Kidney dysfunction
  • Decreased blood clotting
  • Blood sugar fluctuations

Regular overconsumption of lysine can bring problems with blood sugar - it leads to fatigue, listlessness and possibly depression. (Image source: / Ivan Obolensky)

What are the consequences of a lysine deficiency?

In general, a lysine deficiency is very rare. However, if you do not consume enough lysine in your diet, the following negative effects can result:

  • Impairment of the immune system
  • Impaired protein synthesis
  • Growth disorders
  • Susceptibility to infections
  • Anaemia (anaemia)
  • Hair loss
  • brittle nails
  • brittle skin
  • Nausea
  • Loss of appetite, weight loss
  • Mood swings
  • constant tiredness
  • red eyes
  • Lack of concentration/ loss of performance

In the case of slight deficiency symptoms, you can first try to treat these yourself by starting with a balanced diet.

Fish and meat are particularly suitable for this, as lysine is mainly found in animal protein. Vegetarians and vegans can use dietary supplements.

In case of severe deficiency symptoms, you should always consult a doctor and discuss further treatment with him or her.

How do I prevent a lysine deficiency?

You can easily prevent a lysine deficiency by eating a balanced diet. A daily intake of about 3 grams is considered normal. However, this is only an average value.

Your personal lysine requirement depends on your body weight.

Vegans and vegetarians usually have a higher risk of suffering from a lysine deficiency, as only small amounts of lysine are found in plant products.

Lysine is found in large quantities in fish and meat, but also in milk, nuts and vegetables. Accordingly, the daily requirement can be met quite easily with a proper mixed diet.

Due to the fact that lysine is crucial for growth, children and infants have a significantly higher lysine requirement than adults. Here is a small overview:

Age group Lysine requirement per kilogram body weight
Adults 0.016 g
Children 10-12 years 0.044 g
Children 2-5 years 0.058 g
Infants 0-12 months 0.103 g

What foods contain how much lysine?

Whether it's dairy products, nuts, meat, fruit or vegetables: lysine is hidden in countless foods. Here is a list with some examples:

Plant foods Amount of lysine per 100g Animal foods Amount of lysine per 100g
Soybeans 1.9 g Tuna 2.2 g
Dried peas 1.8 g Pork tenderloin 2.2 g
Oatmeal 0.5 g Chicken breast 2 g
Walnuts 0.4 g Salmon 1.9 g
Rice 0.3 g Chicken egg 0.9 g
Lentils 1.9 g Whole milk 0.3 g
Apple 0.015 g Goose 1.3 g
Lemons 0.035 g salami 1.7 g
banana 0.057 g beef 2 g
wheat flour 0.3 g pork liver 1.8 g
tomatoes 0.03 lobster 2 g
kale 0.24 g shrimp 2 g
Potato 0.13 g Eel 1.4 g
Peanuts 1.1 g Oysters 0.7 g
Curd cheese 1.1 g Redfish 1.9 g
Gouda 2.8 g Sardines 2.2 g

The amino acid lysine is found in countless foods, so that even a balanced diet protects against a lysine deficiency. (Image source: / dbreen)

How do I treat a lysine deficiency?

If you suffer from a lysine deficiency, you should definitely change your diet. Furthermore, you will probably have to take additional lysine supplements (depending on the severity of the deficiency).

If you have a severe lysine deficiency, your doctor may also prescribe infusions and special foods with the amino acid, which you can then buy at the pharmacy with your doctor's prescription.

When is lysine used as medicine?

Lysine has many important and positive effects on the human body and is therefore also used in specific areas of medicine, including:

  • to strengthen the immune system
  • for artificial nutrition
  • as an accelerator for the painkiller ibuprofen
  • to combat herpes
  • to improve insulin resistance
  • to improve the cardiovascular system
  • to combat osteoporosis
  • for wound healing

How should I take and dose lysine?

Ideally, you should take lysine simply through a balanced diet, whereby a daily dose of about 3 grams is appropriate on average.

However, if you want to counteract a deficiency or other symptoms by consuming L-lysine supplements, you should check with a doctor, as it is not possible to give an exact dose that is suitable for everyone.

This is because your own need for lysine depends on your body weight.

Did you know that lysine was first used in 1889?

In 1889, lysine was isolated for the first time from a milk protein (casein) and since then the composition of proteins has been studied very thoroughly and their functions in the body researched.

Lysine supplements should be taken as directed in the package leaflet or as prescribed by your doctor.

For the prophylaxis of herpes, 0.5 to 1.5 grams of lysine are usually recommended, and you should preferably combine this with zinc and vitamin C.

To fight herpes, it is advisable to take a dose of 3 grams of lysine.

When should I refrain from taking lysine supplements?

Since an increased intake of lysine can result in a reduction of blood clotting, patients who are about to undergo surgery, for example, should refrain from taking therapeutic doses (i.e. doses that exceed the daily requirement and serve to treat complaints).

Pregnant women and nursing mothers should also avoid such therapeutic doses, as the exact effects on the child are not yet known.

What are the final characteristics of lysine and what are its advantages and disadvantages?

Lysine is characterised by the fact that, unlike many other amino acids, it cannot be produced by the body itself and is thus essential, but at the same time indispensable for the human organism.

  • is found in many foods
  • lysine preparations can be purchased quite cheaply
  • important building block of the human organism
  • well tolerated
  • Vegans and vegetarians often have to resort to preparations
  • long-term overdose can cause damage

What alternatives are there to the amino acid lysine?

Currently, there is no direct alternative to the vital amino acid lysine, which is why it is also considered indispensable.

Where can I buy lysine?

In Germany, you can buy lysine products mainly in pharmacies and online shops, but you can also find them in some drugstores.

Lysine preparations are generally relatively cheap. The prices of different preparations range between four and twenty euros.

Decision: What are the intake options for lysine and how do they differ?

What distinguishes foods and their advantages and disadvantages?

The best and easiest option is to take in lysine through food. A balanced diet is sufficient to avoid suffering from a lysine deficiency.

However, if you want to use lysine to counteract certain ailments, you should make sure you take a higher dose than usual.

  • found in many foods
  • well-tolerated foods
  • found in both plant and animal foods
  • no tedious dosing, easy to take
  • suitable for prevention
  • relatively little lysine is found in plant foods
  • vegans and vegetarians often have to resort to preparations

What are the advantages and disadvantages of tablets and capsules?

Tablets and capsules are quite easy to integrate into everyday life and usually do not cost too much.

You can easily and conveniently take lysine in the form of tablets or capsules with a glass of water or another liquid.

  • relatively inexpensive
  • easy to integrate into everyday life
  • can be taken at any time
  • easy to acquire
  • also suitable for prevention
  • swallowing tablets and capsules can seem unpleasant (especially for children, the elderly and patients with swallowing difficulties)

What are the advantages and disadvantages of chewable tablets?

Chewable tablets are tablets that are bitten, chewed or sucked in the mouth and then swallowed.

This makes them a good alternative for children and people who cannot or do not want to swallow ordinary tablets.

For better tolerance, it is recommended to drink something after swallowing (even if it is not necessary).

  • easy to integrate into everyday life
  • quick and uncomplicated to take on the go
  • easy to purchase
  • also suitable for prevention
  • more expensive than normal tablets or capsules

What are the characteristics of ointments, creams and gels and what are their advantages and disadvantages?

Furthermore, ointments and similar products containing lysine are suitable for the treatment of cold sores.

Simply apply the ointment, cream or gel to the affected area.

  • usually colourless and therefore not visible
  • quick and easy to use
  • can be used at any time if needed
  • easy and sometimes quite cheap to buy
  • only for treating cold sores

What are the advantages and disadvantages of drinking ampoules?

Lysine drinking ampoules are another option for treating cold sores. The ampoules are dosed ready to drink and are therefore very suitable for on the go.

You take one ampoule for treatment as needed (unless otherwise prescribed or stated in the package leaflet).

  • quick and easy to take
  • ready-to-drink
  • can be taken at any time
  • more expensive than other lysine preparations
  • only for treating cold sores

What are the advantages and disadvantages of lysine powder?

If you want, you can take lysine in powder form.

All you have to do is dissolve the powder (about two tablespoons, unless otherwise stated) in water or another drink and take it several times a day at regular intervals.

  • easy to integrate into everyday life
  • uncomplicated to take
  • quite easy and cheap to buy
  • possibly unpleasant taste
  • cannot be taken at any time

Criteria for deciding what to buy: You can use the following criteria to compare and evaluate lysine preparations from different manufacturers

In the following we would like to show you which factors you can use to compare and evaluate lysine preparations. This will make it easier for you to decide whether a particular lysine preparation is suitable for you or not.

In summary, these are:

  • Tolerability
  • Efficacy
  • Price
  • Vegan / Organic?
  • Quality


Taking lysine preparations is usually well tolerated and should therefore not cause any negative complaints, regardless of the manufacturer.

Only a regular overdose can have a negative effect on your kidneys, blood sugar and blood clotting.


The effectiveness of the preparation depends on the concentration of the active ingredient and the dosage.

It is best to discuss your individual lysine requirements with your doctor and then choose a preparation that is suitable for your needs.


Such preparations (tablets, capsules, etc.) are generally quite cheap. In most cases, you can get them for just a few euros.

So you don't have to pay a lot of money for such tablets or capsules. However, always keep an eye on the price-quantity ratio.

Most of the time it is worth buying larger quantities for not much more money.

Vegan / Organic?

If you lead a vegan lifestyle or place a high value on organic products, you are probably wondering whether L-lysine preparations are suitable for your diet.

Most supplements are suitable for both vegans and organic lovers.

However, to be on the safe side, you should make sure that the manufacturer of the product promises this when you buy it.


You should make sure that the lysine preparations have recognised quality seals and are therefore of good quality, as this ensures that the best possible effect is achieved.

It is better to stay away from low-quality products with poor ratings, as they may be adulterated and have negative effects.

In the end, you have to decide for yourself which of the criteria is more important to you and choose the right product accordingly. It is best to ask your doctor or pharmacist for advice.

Trivia: Facts worth knowing about lysine

Lysine as an accelerator

Probably everyone knows the painkiller ibuprofen, which is used to treat mild to moderate pain.

However, ibuprofen is difficult to dissolve, which is why it can only be absorbed slowly by the body.

Lysine can help here, because if the painkiller is combined with the amino acid, the active ingredient can dissolve better and thus enter the bloodstream much faster.

After taking ibuprofen with lysine, the effect can already be felt after ten to fifteen minutes.

The lysine not only makes the ibuprofen work faster, but lower doses of the painkiller are also sufficient to relieve existing pain.

In addition, the pain-relieving effect lasts longer with lysine, which means that fewer tablets need to be taken.

Lysine against herpes

Herpes is an infection caused by a virus in which painful and annoying small blisters form. Although these heal, they can form again at any time because the virus remains in the body for life.

However, these herpes viruses need an amino acid produced by the body, known as arginine, to grow.

It is known that lysine and arginine interfere with each other and displace each other.

Therefore, one thing is certain: the more lysine is taken, the lower the occurrence of arginine and thus curbs the growth of the herpes viruses.

Therefore, it is recommended to take about 3 grams of lysine in order to alleviate herpes and its symptoms.

The effect also works the other way round: if you take more arginine, the number of lysine amino acids in your body decreases and the herpes worsens.

Lysine is considered a proven remedy for fighting herpes. (Image source: / silviarita)

Lysine in animals

Lysine is not only an important amino acid for humans, but also for animals.

Horses in particular often suffer from an L-lysine deficiency and since this amino acid is indispensable for growth, muscle development and wound healing, it is very important as a horse owner to make sure that the horse (especially young horses, since they need more protein than adult horses) consumes enough lysine.

A protein intake that is too low can have serious consequences:

  • reduced food intake
  • Growth disorders
  • bad coat

Lysine is also used in cats to counteract respiratory problems and eye or conjunctivitis.

How is lysine produced?

Basically, lysine is produced biotechnically. The so-called fermentation method is used, whereby organic substances are converted into acid, gases or alcohol.

The bacterium Corynebacterium glutamicium is used to produce lysine. Using this method, more than one million tonnes of lysine are produced annually, which are then further processed as preparations or animal feed.

Image source: / monicore