Introduction
Quassia refers to medicinal preparations derived from the wood of Quassia amara (Surinam quassia) or Picrasma excelsa (Jamaican quassia) trees. These tropical plants have been used traditionally in herbal medicine for centuries, primarily for their bitter properties and potential antiparasitic effects. While not an FDA-approved pharmaceutical drug, quassia preparations are available as dietary supplements and traditional remedies.
Mechanism of Action
Quassia contains several active compounds, primarily quassinoids (including quassin and neoquassin), which demonstrate multiple pharmacological activities:
- Bitter tonic effect: Stimulates bitter taste receptors, leading to increased salivary and gastric secretions
- Antiparasitic activity: Quassinoids exhibit potent activity against various parasites, particularly Enterobius vermicularis (pinworms)
- Insecticidal properties: Acts as a natural insecticide through neurotoxic effects on insects
- Potential anticancer effects: Some quassinoids demonstrate cytotoxic activity against cancer cell lines in preclinical studies
Indications
Note: These are traditional uses not evaluated or approved by regulatory agencies- Traditional treatment for intestinal parasites, particularly pinworms
- Appetite stimulation in cases of anorexia or digestive weakness
- Management of dyspepsia and gastrointestinal complaints
- Topical use for head lice infestations
- Folk use as a febrifuge (fever reducer)
Dosage and Administration
Forms available: Tinctures, extracts, powders, and teas Typical adult dosing:- Tincture (1:5 in 45% alcohol): 1-3 mL three times daily
- Infusion: 1-2 grams of dried wood in 150 mL boiling water, steeped 10-15 minutes
- Powder: 0.5-2 grams daily
- Take 15-30 minutes before meals for appetite stimulation
- For parasitic infections: typically administered for 7-10 days
- Topical applications for lice: apply as directed, avoiding eye area
- Pediatrics: Safety not established; traditional use suggests reduced doses
- Pregnancy/lactation: Contraindicated due to lack of safety data
- Hepatic/renal impairment: Use with caution
Pharmacokinetics
Limited human pharmacokinetic data exists. Preclinical studies suggest:
- Absorption: Poor oral bioavailability due to high molecular weight and polarity of quassinoids
- Distribution: Not well characterized; likely limited tissue distribution
- Metabolism: Hepatic metabolism suspected but not well documented
- Elimination: Primarily renal elimination; elimination half-life not established
Contraindications
- Pregnancy and breastfeeding
- Known hypersensitivity to quassia or related species
- Severe hepatic impairment
- Peptic ulcer disease
- Inflammatory bowel conditions
Warnings and Precautions
- Hepatotoxicity: Cases of liver injury have been reported with prolonged use
- Gastrointestinal effects: May cause nausea/vomiting in sensitive individuals
- Neurological effects: High doses may cause visual disturbances
- Drug quality: Variability in commercial preparations may affect safety and efficacy
- Long-term use: Not recommended beyond 4 weeks without medical supervision
Drug Interactions
- Anticoagulants: Potential additive effects due to possible coumarin content
- Diabetes medications: May affect blood glucose levels
- CNS depressants: Theoretical potential for additive sedative effects
- Substrates of CYP enzymes: Possible inhibition of cytochrome P450 enzymes
Adverse Effects
Common:- Gastrointestinal discomfort
- Nausea
- Bitter taste sensation
- Hepatotoxicity (elevated liver enzymes, jaundice)
- Visual disturbances
- Severe vomiting
- Allergic reactions
Monitoring Parameters
- Liver function tests (with prolonged use)
- Complete blood count (with extended therapy)
- Visual acuity assessments (if visual symptoms occur)
- Therapeutic efficacy for intended use
- Adverse effect profile
Patient Education
- Inform healthcare provider of use, especially if taking other medications
- Discontinue use if jaundice, dark urine, or abdominal pain occurs
- Use only standardized preparations from reputable sources
- Do not exceed recommended dosage or duration
- Not for use during pregnancy or breastfeeding
- Keep out of reach of children
- Report any visual changes immediately
References
1. Gertsch J, et al. How scientific is the science in ethnopharmacology? Historical perspectives and epistemological problems. J Ethnopharmacol. 2009. 2. Osorio EJ, et al. Quassinoids: Structural diversity, biological activity and synthetic studies. Stud Nat Prod Chem. 2016. 3. Muhammad I, et al. Bioactive natural products from medicinal plants. Stud Nat Prod Chem. 2005. 4. European Medicines Agency. Assessment report on Quassia amara L., lignum. 2012. 5. Natural Medicines Database. Quassia Professional Monograph. 2023. 6. McGuffin M, et al. American Herbal Products Association's Botanical Safety Handbook. CRC Press, 2013.
Note: This monograph provides information on traditional use patterns. Quassia preparations are not FDA-approved drugs and should be used under appropriate professional guidance. Clinical applications should be based on risk-benefit assessment considering available evidence.