herb · for lack of focus
Rhodiola
Steadies your stress response and supports the brain chemicals that hold attention.
Say that in clinical terms
Rhodiola modulates HPA axis activity and enhances monoamine neurotransmitter levels (dopamine, serotonin, norepinephrine), supporting mental stamina and sustained attention during cognitively demanding tasks.
How strong is the research?
Solid evidence
Studied in a narrower groupIndustry funded
4 papers read, 2 supporting.
Tested as: standardised Rhodiola rosea root extract SHR-5
Who was studied: Adults aged 20 to 55 who met clinical criteria for fatigue syndrome.
How much to take
daily in the morning
200–400 mg
Best taken early in the day. Standardized to 3% rosavins and 1% salidroside.
Before you take it
- No Tolerable Upper Intake Level (UL) has been established by NIH ODS for Rhodiola rosea — it is an herbal supplement without a formal UL; NCCIH considers it possibly safe for up to 12 weeks at studied doses (typically 200–600 mg/day).
- Safety in pregnancy and lactation is unknown; NCCIH states 'little is known about whether it is safe to use rhodiola during pregnancy or while breastfeeding'; clinical use during these periods should be avoided.
- In vitro inhibition of CYP3A4 and CYP2C9 confirmed (MSK Integrative Medicine); may reduce clearance of drugs with narrow therapeutic index metabolized by these enzymes, including warfarin, phenytoin, immunosuppressants, and antiretrovirals; clinical significance in humans is not formally established.
- Inhibits P-glycoprotein (P-gp) in vitro (MSK); may alter bioavailability or plasma concentrations of P-gp substrate drugs.
- MAO-A and MAO-B inhibitory activity demonstrated in vitro; avoid concurrent use with MAOIs; exercise caution when combined with SSRIs, SNRIs, or other serotonergic agents — a case report documented tachyarrhythmia in a patient combining Rhodiola with antidepressants.
- Interaction with losartan (an antihypertensive) has been reported by NCCIH; caution is warranted in patients on blood pressure medications.
- Common adverse effects at studied doses: dizziness, dry mouth, headache, and insomnia.
- No clinical safety data exist beyond 12 weeks of continuous use.
When to take it
Best taken: morning