Who Makes Kirkland Signature Sleep Aid, And Is It Good For You?

Regardless of how well you stick to your sleep routine, sometimes you need a little help from a sleep aid when life is a little chaotic. Sleep supplements like melatonin help your body settle into a more consistent sleep/wake cycle, and minerals like magnesium help relax your muscles and nerves to set you up for a good night's rest. Herbal remedies and amino acids also work to bring more calm to your body and mind (here are some other tricks to try if you can't fall asleep). 

Over-the-counter sleep aids are often antihistamines that also have a sedative effect. Kirkland Signature Sleep Aid is a popular over-the-counter solution for occasional sleeplessness, found exclusively at Costco stores. It's made by pharmaceutical company LNK International, Inc.

Kirkland Signature Sleep Aid's active ingredient, doxylamine succinate, is a well-known antihistamine that's also found in Unisom Sleeptabs. Although this sleep aid is considered safe for short-term sleeplessness, you should be aware of some of doxylamine's side effects and drug interactions.

Doxylamine works by blocking histamine, a chemical your body releases during immune responses. Histamine is what causes allergy symptoms like a stuffy nose or watery eyes. While blocking histamine can relieve allergies, it also makes you drowsy, which is why it's effective as a sleep aid.

However, like most medications, doxylamine comes with a list of potential side effects. Common ones include nausea, constipation, and dryness in your mouth, nose, and throat. Some people may also experience chest congestion, headaches, dizziness, or blurred vision. Interestingly, even though doxylamine is a sedative, it can sometimes have the opposite effect, causing nervousness or excitement instead.

More serious side effects, though rare, can include hallucinations, confusion, severe dizziness, or difficulty urinating. These are more likely to occur in older adults, so they should use doxylamine with caution.

You'll also need to be mindful of drug interactions. If you're taking other medications that cause drowsiness, such as cold and flu remedies or other sedatives, combining them with Kirkland Signature Sleep Aid could amplify the effects. And let's not forget alcohol — it's a big no-no when using sleep aids (and alcohol can ruin your sleep).

If you're dealing with urinary issues, doxylamine might not be the right fit for you since it can make urination more difficult. People with conditions like an enlarged prostate, glaucoma, or lung issues such as asthma should consult a doctor before taking this sleep aid. Pregnant individuals should also check with their doctor, and if you're breastfeeding, it's best to avoid doxylamine altogether, as it could harm your baby.

Another important point: don't use sleep aids like doxylamine unless you've got a full night to devote to rest. The medication typically kicks in within 30 minutes, so be ready to hit the pillow. You might also feel groggy the next morning, especially if you didn't get enough sleep. Kirkland Signature Sleep Aid contains 25 milligrams of doxylamine per dose — stick to just one tablet per night.

Sleep aids like doxylamine are fine for short-term use, but if insomnia persists for more than two weeks, it's time to see a doctor. Long-term use can lead to psychological dependence, where you feel like you can't sleep without the medication. It might actually make your insomnia worse when you try to stop.

There are also potential long-term risks of cognitive decline later in life. A 2021 study in Sleep Medicine found that routine use of sleep aids could increase the risk of dementia by 30%.