These Popular OTC Supplements May Cause Insomnia

by Martin Reed Patient Advocate

Getting a good night's sleep is important for physical and emotional health, as well as energy levels. But for many Americans today, quality sleep is something that is increasingly difficult to achieve.

Many of the reasons for insomnia are well-known, such as health issues, shift work, stress levels, poor quality bedding and problems associated with prescription medications.

To address these problems, many of those who deal with poor sleep quality turn to over-the-counter (OTC) supplements that promise to promote better sleep with no side effects. In addition, many people who are taking OTC supplements for other reasons, such as weight loss or to boost overall health, may be inadvertently affecting their sleep quality.

If you frequently suffer from insomnia and take OTC supplements for any reason, the following list will give you a starting point to help you determine if the supplements you are taking could be affecting your sleep.


Guarana is a supplement that has become increasingly popular with people seeking to lose weight due to its stimulating properties. It originates from South America where it is harvested as a berry.

Known to increase thermogenesis in the body, the guaranine found in guarana can create an effect much like caffeine. It can also increase anxiety levels and cause other reactions that are known to impact sleep quality.

Insomnia is a known side effect of Guarna, which contains caffeine. It is important to be careful to read labels of energy drinks or supplements that contain guarna to understand the amount of caffeine per serving. It is best not to combine guarna with other sources of caffeine to avoid a caffeine overdose that may cause shakiness, dizziness and worsen insomnia.


Often used to improve stamina, mental alertness and concentration levels, this supplement can cause many health issues when taken in higher than recommended doses.

Insomnia is just one of the potential side-effects for those taking OTC ginseng supplements. Others include changes in heart rate and blood pressure, headaches, dizziness, diarrhea and loss of appetite.

Green Tea

Often used as a supplement both as capsules, as well as tea bags or tea leaves, green tea is thought to have many positive influences on the body. These include:

  • Aiding metabolism

  • Increasing mental alertness

  • Regulating blood sugar levels

Unfortunately, because green tea contains a significant amount of caffeine, it can cause insomnia, as well as dizziness, heart palpitations, diarrhea and nausea.

Taking Supplements Safely

If you are planning to take these supplements, or any other, you should take the following steps to ensure that you do so safely:

  • Discuss the supplements you plan to take and your reasoning for wanting to take them with your doctor

  • Ensure that any supplements purchased are produced by a reputable manufacturer

  • Follow dosage directions carefully

  • Use a calendar or journal to jot down the dates, dosages and any side effects felt while taking the supplements so you can discuss them with your healthcare professional

Although occasional sleepless nights is common for most people, any instance of prolonged or excessive insomnia should always be taken seriously.

Your healthcare provider can help you determine why you are experiencing insomnia and help you find the best solution to address the problem.

Martin Reed
Meet Our Writer
Martin Reed

Martin is the creator of Insomnia Coach, an eight-week course that combines online sleep education with individual sleep coaching. His course helps clients improve their sleep so they can enjoy a better life with more energy and start each day feeling happy, healthy, rested, and refreshed. Martin also runs a free sleep training course that has helped over 5,000 insomniacs. He holds a master’s degree in health and wellness education and studied clinical sleep health at the University of Delaware.