L-Theanine Side Effects

Theanine is a naturally occurring substance that is commonly is extracted from green tea. It is touted as an all round supplement that helps prevent anxiety and relaxes the mind and yet doesn’t cause drowsiness, it also has immune boosting properties and lowers the blood pressure. It is a rare supplement, and an even rarer drug that can be said to have no proven negative side effects such as L-Theanine. Studies performed with Theanine have established strong benefits but have been unable to substantiate this supplement has any negative side effects.

L-Theanine Side EffectsHowever, there might be some possible interactions when using L-Theanine that can cause problems. Thus far, there is no research indicating that Theanine is problematic when used with any pharmaceutical.
L-Theanine has been the subject of a 1995 rat study where groups of rats with high blood pressure were given Theanine. The group of rats with high blood pressure had their blood pressure reduced with the supplement, and just as significantly, the same study indicated that the control group, rats with normal blood pressure did not experience a drop in blood pressure when given Theanine.  However, individuals taking hypertensive drugs should probably consult a medical professional before using this supplement because although Theanine doesn’t seem to affect normal blood pressure, medications for hypertension may not be as selective. Combining a drug for hypertension with Theanine might possibly produce unwanted side effects.

L-Theanine is also known for its relaxant properties. This effect is produced without the usual drowsiness that accompanies even natural relaxants. Generally, L-Theanine is said to produce a relaxed but alert mental state with more Alpha Waves. However, if an individual is also taking sedatives or hypnotics their effect might be magnified. Depressants such as alcohol might also enhance that. Again, there are no studies that indicate this is a potential side effect but anyone taking hypnotics may wish to consult with a medical professional before adding L-Theanine supplements.

Individuals, who take medications that are intended to have a stimulant effect on the nervous system and which tend to make them jittery, may that side effect reduced since L-Theanine has a calming effect. Whether this is a negative side effect or not depends on the medication and purpose, but it is a possible interaction. No conclusive studies have been done in this area since feeling jittery or anxious is rarely considered a desirable state.
Although it is not possible to find conclusive evidence or even suggestive studies that L-Theanine has negative side effects, every person is different and their reaction to any supplement can vary. As with any supplement, a medical professional’s advice should be sought before administering it to children or pregnant women.  Some consideration should also be given as to possible interactions with prescription medications such as those used to treat high blood pressure or any medication intended to relax or calm an individual. In general, Theanine is a naturally occurring supplement considered very safe and which can produce benefits with few side effects in the average adult.