Studies on valerian as a sleep aid have come to mixed conclusions on the herb’s effectiveness, which may be related to varying amounts of its active components in different products. But almost across the board, studies have concluded that for most people, valerian is safe, with few serious side effects reported. (1) But that doesn’t mean there are no risks to taking this supplement. Long-term studies of valerian are few and far between, so it’s unknown whether there are health risks associated with taking it regularly for years. Even when it comes to known risks associated with valerian, there are reasons to be cautious with this herb. Here’s what we know about the side effects valerian can have, and when you may want to reconsider taking it.
Common Side Effects of Valerian
In all the clinical studies of valerian, there have been few reported serious side effects, according to the National Institutes of Health. What’s more, many of the most commonly reported side effects also occurred in people who took a placebo, or inactive pill. (1) The most common side effects associated with valerian include:
HeadachesDizzinessSkin itchingDigestive upsetAbnormal heart rhythm (1,2)
Because valerian is often taken as a sleep aid, drowsiness is usually considered a desired outcome rather than a side effect. But if you’re taking it in smaller doses to help relieve anxiety, you should be aware that it might also make you somewhat sleepy. For this reason, you shouldn’t take valerian if you’re driving or need to be alert. (2) There’s some evidence that in some people, valerian may increase drowsiness the morning after it’s taken. This may depend on the dose of the supplement you’re taking, with higher doses leading to more drowsiness the next day. (1) Some people have what’s known as a paradoxical reaction to valerian, where it makes them less sleepy and potentially causes insomnia. If you take valerian at bedtime and find it more difficult to fall asleep than usual, this may be happening. (2) While the effects of valerian in people with heart rhythm disorders hasn’t been evaluated, the supplement has been shown to slow the heart rate in some people and may cause certain abnormal rhythms. For this reason, you should be very cautious about taking valerian if you have an abnormal heart rhythm. Valerian isn’t known to interfere with sleep cycles or restful sleep, but this may not be the case if it causes insomnia. If you find yourself drowsy the next morning, it may be because your dose was too high, or because valerian made it more difficult for you to sleep. (1,2)
Possible Drug Interactions With Valerian
Just like conventional medicines and drugs, dietary supplements can interact with other supplements or drugs that you take. For this reason, it’s important to discuss taking valerian with your doctor if you take any other drug or supplement on a regular basis. (2) Because valerian can increase sleepiness, you shouldn’t take it in combination with any other drug or supplement used to increase relaxation or treat anxiety or depression — unless you’re doing so under medical supervision. These drugs and supplements include:
Benzodiazepines such as alprazolam (Xanax), diazepam (Valium), lorazepam (Ativan), or triazolam (Halcion)Barbiturates such as phenobarbital (Luminal) or propofol (Diprivan)Antidepressants or anxiolytics, including selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants (TCAs), and monoamine oxidase inhibitors (MAOIs)Opiates or narcotics, such as codeine, hydrocodone (Vicodin), oxycodone (OxyContin), acetaminophen and oxycodone (Percocet), methadone, or morphineAny prescription or over-the-counter (OTC) sleep aids, including zolpidem (Ambien), eszopiclone (Lunesta), and zaleplon (Sonata)Dietary supplements including St. John’s wort, kava, and melatonin (1,2)
Alcohol is a depressant that can have a sedative effect in some people, which may be increased when combined with valerian. Don’t drink alcohol if you take valerian during the day, unless you know how this combination affects you. If you drink alcohol in the evening, you should be aware that this could increase the effects of valerian at night. (3)
Who Shouldn’t Take Valerian
It’s always recommended to talk to your doctor before taking any new dietary supplement. This is especially true for valerian if you take any other drugs or supplements. Certain groups of people shouldn’t take valerian, including:
People with liver diseaseWomen who are pregnant or breastfeedingChildren under 3 years old (1,3)
The potential effects of valerian on a developing fetus or newborn baby haven’t been evaluated, so it’s safest to avoid this supplement if you’re pregnant or breastfeeding. Likewise, the effects of valerian in young children haven’t been evaluated, so it shouldn’t be given to children.
