Warnings About Taking Skullcap

Skullcap is a term used to refer to two different herbs. American skullcap, or Scutellaria lateriflora, is an herb native to North America, and is used as a tranquilizer and sedative, according to the University of Maryland Medical Center 1. Traditional Chinese physicians recommend Chinese skullcap, or Scutellaria baicalensis, as a remedy for headaches, infections and allergies. These herbs may cause several side effects and other health problems.

Drowsiness

American skullcap is a powerful sedative, according to Michael Castleman, author of "The Healing Herbs." This herb may cause drowsiness 2. You should not take skullcap during waking hours, particularly if you plan to drive a car or operate heavy machinery.

Hypoglycemia

The chemical compounds in Chinese skullcap may lower blood glucose, according to the University of Maryland Medical Center 1. Low blood glucose, or hypoglycemia, may produce symptoms such as:

• fatigue
  
• mental confusion
  
• disorientation
  
• muscle weakness
  
• fainting

Avoid Chinese skullcap if you have hypoglycemia or diabetes.

Seizures

Concentrated amounts of the chemical compounds found in American skullcap may contribute to seizures, muscle twitches and convulsions, according to Castleman. You may have an increased risk of seizures if you use this herb in tincture form, which contains high amounts of these chemicals. Avoid using American skullcap tinctures if you have epilepsy or nerve damage.

Other Side Effects

American skullcap may cause feelings of giddiness or euphoria, according to the University of Maryland Medical Center 1. It may also cause arrhythmia, or irregular heartbeat. You may also experience diarrhea or stomach upset when using American skullcap, notes Castleman.

Chinese skullcap may cause stomach pains, and it could damage your spleen.