Valerian Side Effects Are Rare but Sometimes Require Extra Care

Valerian is one of the herbs that used to be known as the "seven sisters of sleep." Prescribed by herbalists for use with hops or passionflower, valerian is very nearly free of side effects, but valerian side effects may require extra care when driving a car or operating heavy machinery.

Finding the Right Valerian Dosage

Most people don't give a lot of thought about how much valerian to take. They just take one capsule or one dropper full if it usually works right away, and two capsules or two droppers full if it doesn't.

And most of the time, this works. However, there is a more precise way to go about dosing valerian. Here are the general guidelines:

Valerian Flower

There are a lot of variables in determining how much valerian is enough and how much is too much.

Valerian Overdose

Valerian overdose is not very likely, unless you are taking other sleeping aids. Like most herbs, valerian overdosing is a problem primarily when you are taking it for the first time with other sleeping pills or you are taking it after your doctor changed your dosage of another sleeping pill.

It's always best to use valerian by itself to avoid overdosing. At least avoid starting valerian the same week your doctor has upped the dosage of any prescription sleep medication.

What about Valerian Interactions?

The obvious valerian interactions are with alcohol, benzodiazepine tranquilizers, and barbiturates. Since these agents help you sleep and valerian also helps you sleep, combining them can result in next-day drowsiness, increased risk of accidents while driving or operating heavy machinery the next day, or, in the worst case, difficulties breathing.

The not-so-obvious interactions of valerian with prescription drugs are those that occur because of the way the liver processes the active chemical compounds in this herb.

The liver uses an enzyme called CYP450 3A4 to process the valeopotriates in valerian that help you get to sleep. The liver also uses this enzyme to process statin drugs for cholesterol, the active chemical in red yeast rice, some chemicals used to treat yeast and fungal infections, and certain tranquilizers.

Theoretically, taking valerian could cause the listed medications to build up in the bloodstream. In the real world, this has never been observed, but it is still a good idea to err on the side of caution and avoid taking valerian if you take any prescription drugs in these classes.

Other Possible Adverse Effects of Valerian

The common term used to describe the herb valerian in the Latin language during the time of the Romans was the exclamation "Phu!" Valerian is not a sweet-smelling herb. Some people find valerian teas make them just a little nauseous because of the smell. If that is a problem, just take capsules instead.

Valerian Herb

Some people have allergic reactions to valerian. In rare cases, it can cause itchy rashes or reddening of the skin. If you have an allergic susceptibility to valerian, you will probably notice these reactions when you take your very first dose. If you experience these reactions after you have been taking valerian for weeks or months, the allergy is probably caused by something else.

Headaches, chest palpitations, and unusual sweating occur in a very small number of people who take valerian. There also have been cases of liver toxicity, but these cases involved people who already had viral hepatitis or other chronic liver disease.

Who Should Not Take Valerian?

Valerian is generally considered appropriate for adults only. People who should not take this herb include:

Frequently Asked Questions about Valerian Side Effects

Q. Is valerian safe during pregnancy? Is valerian safe for kids? Is valerian root safe while breastfeeding?

A. The answer to all of these questions is no. Although there is no evidence valerian is harmful in these situations, there is no proof it is safe. Err on the side of caution and avoid giving valerian to children or taking valerian while pregnant or breastfeeding.

Q. Is valerian root addictive?

A. No, although I have heard of one case of a man who was taking Mirapex for Parkinson's disease who got such a boost to libido from taking valerian (it's the combination of the drug and the herb that does this) that he only stopped taking the herb when was no longer able to drive to the natural products shop to get it. (We didn't tell him it was available online.)

Q. Are there any uses of valerian other than helping you go to sleep?

A. Traditionally, this herb has been used for treating menstrual cramps, hot flashes during menopause, "nervous" asthma, hysterical states, migraine headaches, and hypochondria. Before 1900, the herb was also given to children who displayed what we would not call "attention deficit hyperactivity disorder." There have not been any scientific studies of valerian for these applications, although it's not likely to hurt to use the herb as long as you continue to take any prescribed medications. Always let your doctor know about any herbs you take or plan to take.

Q. Will valerian "put me out like a light?"

A. No, valerian usually reduces sleep latency, the amount of time it takes to fall asleep. Typically people can go to sleep within about 10 to 15 minutes after going to bed when they take valerian.

Q. Are there any sleeping pills that I should not take with valerian?

A. It's important to work with your doctor on choices of medications and dosing of medications. Don't try a little of this and a little of that to see if it works. Take your prescribed medication until you and your doctor decide to discontinue it.

That said, any sleeping aid that is also a muscle relaxant can prove to be too much when combined with valerian (or herbal mixtures of valerian, hops, and/or passionflower). The combination of valerian and a benzodiazepine tranquillizer can cause paradoxical effects such as insomnia, worsening of symptoms of borderline personality disorder, or, in people who have epilepsy, increased frequency of seizures.

Q. Please list the names of the benzodiazepine tranquilizers, so I'll know not to take valerian.

A. Here's a list by generic name and major brand names. I've made an effort to contain major brand names that are used in about 95% of the world, but some benzodiazepine drugs may not be on this list. Ask your pharmacist to be sure.

Alprazolam Xanax, Xanor, Kalma, Tafil, Frontal, Alprox

Bromazepam Lexotanil, Lexotan, Bromam, Lexomil, Somalium

Chlordiazepoxide Librium, Tropium, Klopoxid, Risolid

Cinolazepam Gerodorm

Clobazam Frisium

Clonazepam Klonopin, Rivotril

Cloxazolam Olcadil

Clorazepate Tranxene

Diazepam Valium, Vival, Apzepam, Stesolid, Apozepam, Ducene, Hexalid, Valaxona, Antenex

Estazolam ProSom

Flunitrazepam Rohypnol, Ronal Fluscand, Flunipam, Hypnodorm, Rohydorm (Brazil)

Flurazepam Dalmane

Halazepam Paxipam

Ketazolam Anxon

Loprazolam Dormonoct

Lorazepam Ativan, Lorabenz, Temesta

Lormetazepam Loramet, Noctamid, Pronoctan

Medazepam Nobrium

Midazolam Dormicum, Versed, Dormonid, Hypnovel

Nitrazepam Mogadon, Pacisyn, Dumolid, Alodorm

Nordazepam Madar, Stilny

Oxazepam Seresta, Serenid, Serepax, Sobril, Oxascand, Alopam, Oxabenz, Oxapax, Murelax, Alepam


Pinazepam Domar

Prazepam Centrax

Quazepam Doral

Temazepam Restoril, Normison, Nocturne, Temaze, Euhypnos, Temtabs

Tetrazepam Mylostan

Triazolam Halcion, Rilamir