University of Iowa Adult Outpatient Psychiatry Department
(319) 353-6314. After hours: (319) 356-1616
2/13/2016
ST.JOHN’S WORT
St.John’s wort is used to treat mild to moderate depression and possibly anxiety.
This medication is not recommended for treatment of severe depression, including depression with suicidal
thoughts, psychotic features (hallucinations, confused thoughts), or melancholia (weight loss, early morning
awakening, very low energy).
Proper use of this medication:
There is little information available on this medication in the English literature.
Because over-the-counter herbal medications are not regulated in this country, the purity and potency of any
given brand may vary.
There is no medical research concerning the method of changing from prescription antidepressants to St.John’s
Wort.
Consult with your physician before discontinuing any medication you are currently taking.
Do not start taking St.John’s Wort until you have been off your current antidepressant at least one week (2
weeks if you are taking Nardil/phenelzine or Parnate/tranylcypromine).
The commonly reported dose of extract is 300 - 1000 mg per day. (Most people take 300 mg, 3 times daily.)
The commonly reported dose of hypericin is 0.4 - 2.7 mg per day.
This medication is not addictive, and does not cause a high feeling.
When taken regularly, this medication may require 4-8 weeks before the full effects are noticed.
Do not drink alcohol while taking this medication.
Do not take this medication within 5 days of a surgical procedure.
If there is a possibility you may become pregnant or breast-feed while on this medication, first consult with
your psychiatrist. This drug has not been tested in pregnancy, and it is unknown if it is excreted in breast milk.
This medication should not be abruptly discontinued.
Store this medication in a cool, safe place away from the reach of children.
This medication is usually very well tolerated, with only 2-3% of patients complaining of side effects . Most
studies show no difference in side effects between St.John’s wort and placebo. However reported possible
side effects include:
Anxiety/restlessness: This will usually go away with continued use.
Fatigue: This is uncommon and usually goes away with continued use.
Concentration: Some studies demonstrate improved concentration and attention.
Dizziness: This is uncommon and usually goes away with continued use.
Nausea: Take this medication with food. This usually goes away with continued use.
Weight loss, loss of appetite: This is uncommon and usually goes away with continued use.
Diarrhea or constipation: High-fiber diet and regular exercise may treat this uncommon side effect.
Sun sensitivity: This is a common side effect in animals ingesting St.John’s Wort, but has been uncommonly
reported in humans, as rash or skin pain. Use sunscreen and wear appropriate protective clothing. The effect is
temporary, ending soon after the drug is discontinued.
Allergic reactions: Have been reported in .5% of patients, and include skin rash and itching.
If any side effect persists or becomes intolerable, discuss this with your physician.
The following other medications may require dosage adjustment while taking St.John’s Wort:
Idinavir (Crixivan)
Cyclosporine,
Monoamine Oxidase Inhibitors (Tranylcypromine/Parnate, Phenelzine/Nardil, Isocarboxazid/Marplan).
Serotonin Reuptake Inhibitors (Paroxetine/Paxil, Sertraline/Zoloft, Fluvoxamine/Luvox, Venlafaxine/Effexor),
Warfarin/Coumadin.
Digoxin
St.John's wort may lower the effectiveness of oral contraceptives (birth control pills) .
St. John’s wort may significantly lower oxycodone levels.
Cyclic Antidepressants (Amitriptyline/Elavil, Nortriptyline/Pamelor, Protriptyline/Vivactil,
Clomipramine/Anafranil, Imipramine/Tofranil, Desipramine/Norpramin, Trimipramine/Surmontil,
Amoxapine/Asendin, Doxepin/Adapin/Sinequan, Maprotiline/Ludiomil, Trazodone).
Drugs that may cause sun sensitivity, such as Tetracycline and many anti-psychotic medications.
Do not use phototherapy (bright lights) when taking St.John’s wort.
Further information may be obtained from:
The Hypericum Home Page on the internet at www.hypericum.com.
Webmaster@mhsource.com
Hypericum and Depression, by H Bloomfield, M Nordfors, & P McWilliams.