St. John’s Wort

There is some evidence to suggest that St. John’s wort may be effective in treating mild or moderate depression. There is not enough evidence to support its use in treating other conditions.

St. John’s wort may cause increased sensitivity to sunlight and skin rash. Other side effects can include anxiety, diarrhea, difficulty sleeping, dizziness, dry mouth, gastrointestinal symptoms, fatigue, or headache. In rare situations, it may lead changes in appetite, joint or muscle stiffness, muscle spasms or pain, sexual dysfunction, tremors, developing suicidal thoughts, or abnormal mood changes.

Research shows that St. John’s wort interacts with many medications in ways that interfere with their intended effects. Examples of medications that can be affected include:

• antidepressants, such as serotonin reuptake inhibitors (SSRIs)
• anti-anxiety medications, such as benzodiazepines
• antihistamines
• birth control pills
• blood thinners
• bronchodilators, such as those used to treat asthma or COPD
• cancer medications
• certain diabetes medications (e.g., gliclazide)
• heart medications (e.g., digoxin, procainamide)
• HIV medications
• medications that suppress the immune system (e.g., transplant medications)
• muscle relaxants
• opioid medications
• seizure medications

St. John’s wort is not a proven therapy for depression. If depression is not adequately treated, it can become severe. Anyone who may have depression should see a health care provider. There are effective proven therapies available.

Let your health care provider know before taking St. John’s wort if you:

• are pregnant or breast-feeding
• have a psychological disorder (e.g., Alzheimer disease, anxiety, bipolar disorder, depression, schizophrenia)

Due to St. John’s wort effects on serotonin levels, it may interfere with surgical procedures. Stop taking St. John’s wort at least 2 weeks before any surgical procedures.

While you’re taking St. John’s wort, avoid prolonged exposure to UV light, such as through sunlight or UV light therapy.

Before taking any new medications, including natural health products, speak to your physician, pharmacist, or other health care provider. Tell your health care provider about any natural health products you may be taking.