| 释义 |
Camellia sinensis
Thesaurus| Noun | 1. |  Camellia sinensis - a tropical evergreen shrub or small tree extensively cultivated in e.g. China and Japan and India; source of tea leaves; "tea has fragrant white flowers"teatea leaf, tea - dried leaves of the tea shrub; used to make tea; "the store shelves held many different kinds of tea"; "they threw the tea into Boston harbor"genus Camellia - tropical Asiatic evergreen shrubs or small treesbush, shrub - a low woody perennial plant usually having several major stems |
camellia sinensis
 green tea green teaAn evergreen with an endless supply of tea! Use the young new leaves. Either boil the leaves for 15 seconds or freeze them for 30 minutes, then dry them for later use as tea. Green tea is very high in antioxidants that help protect cholesterol in blood from oxidating and forming free radicals. Green tea is a better antioxidant than either oolong or black tea. These are actually all the same plant, Camellia sinensis. The difference is that green tea is unfermented. Oolong is partially fermented, and black tea is fully fermented. The fermentation process destroys many of the antioxidant polyphenols. White tea, is are also from the C. sinensis plant, but contains the baby leaf buds. Green tea is known for its anti-cancer properties from the antioxidant and antiviral nature of the polyphenols. Green tea also helps with weight loss due to both the xanthines (caffeine, theophylline, theobromine) that act as thermogenics (increases temperature through the increased burning of body fat) and suppresses appetite. Also contains theanine, which has calming action on the body and counters the stimulant action of the tiny amount of caffeine in the plant. Take green tea by itself because it contains substances that can render other herbs or medications useless to the body, including what you eat. Green tea can hinder the absorption of nutrients into the body. Contains tiny amount of flouride, so take a break once in a while. An alternative antioxidant tea to consider is red tea (rooibos, honey bush)...a mild, slightly sweet tea with antioxidant properties 30 times greater than green tea, and very low in polyphenols, so it will not interfere with other herbs or medications. Rooibos is also anti-cancer.Camellia sinensis
black tea (blak tee) blacktea, Camellia sinensis (trade name), English tea (trade name), Theaflavin (trade name) Classification Therapeutic: central nervous system stimulants
Mental alertness HeadacheWeight lossMyocardial infarction and atherosclerosis preventionAction Black tea contains caffeine (2–4%) a methylxanthine that stimulates the CNS through adenosine receptor blockade and phosphodiesterase inhibition, relaxes smooth muscle in the airways, stimulates the heart and has diuretic effects. Theaflavins and tannins present in black tea are responsible for antioxidant properties.Therapeutic effectsCNS stimulation.Diuresis.Elevated heart rate and BP.PharmacokineticsAbsorption: Unknown.Distribution: Unknown.Metabolism and Excretion: Unknown.Half-life: Unknown.Time/action profile | ROUTE | ONSET | PEAK | DURATION |
|---|
| PO | unknown | unknown | unknown |
Contraindications/PrecautionsContraindicated in: Allergy or hypersensitivity to caffeine or tannin; Obstetric: Pregnancy and lactation (in high doses due to caffeine content).Use Cautiously in: Cardiac arrhythmias; Diabetes; Peptic ulcer disease; Osteoporosis (caffeine increases urinary calcium excretion); Iron deficiency anemia (may worsen); Pediatric: Safety and efficacy has not been established in children.Adverse Reactions/Side EffectsCardiovascular- arrhythmia
- hypertension
- tachycardia
Central nervous systemDermatologicEndocrinologicFluid and ElectrolyteGastrointestinal- constipation
- increased stomach acid
Hematologic- iron deficiency
- microcytic anemia
Genitourinary- diuresis
- increased urine sodium, potassium, and calcium levels
Musculoskeletal- rhabdomyolysis (high doses)
InteractionsCimetidine, disulfiram, fluvoxamine, phenylpropanolamine, fluoroquinolones, and estrogens can ↓ caffeine clearance and ↑ adverse effects. Caffeine can inhibit dipyridamole -induced vasodilation.Abrupt withdrawal of caffeine can ↑ lithium levels.Additive stimulatory effects with CNS stimulants.Caffeine can ↑ theophylline levels.May ↑ heart rate and BP when used with bitter orange.May ↑ stimulatory effects when taken with ephedra and green tea.Oral (Adults) Heart disease prevention—1–4 cups daily; Headache/mental performance—1–5 cups daily. One cup of black tea contains approximately 50 mg caffeine. A maximum of 8 cups/day has been suggested.AvailabilityTea leaves: OTCNursing implicationsNursing assessment- Assess BP and heart rate periodically in patients at risk for cardiovascular side effects.
- Lab Test Considerations: Monitor liver and kidney function tests and blood glucose, plasma homocysteine, and uric acid levels periodically in patients with who drink large amounts of black tea.
Potential Nursing DiagnosesAcute pain (Indications)
ImplementationPatient/Family Teaching- Advise patient that chronic use of black tea may be habit-forming. Abrupt discontinuation may lead to withdrawal symptoms; decrease gradually.
Evaluation/Desired Outcomes- Increased mental alertness.
- Increased urine output.
- Decrease in headache pain.
green tea (green tee) greentea, Camellia sinensis (trade name) Classification Therapeutic: central nervous system stimulants
Bladder, esophageal, ovarian and pancreatic cancer risk reduction, mental alertness, hypotension, cervical dysplasia associated with human papillomavirus infection, hyperlipidemia, weight loss, protection of the skin from sun damage, genital warts, dental caries, Parkinson's diseaseActionCaffeine in green tea stimulates the CNS and cardiovascular system through adenosine receptor blockade and phosphodiesterase inhibition.Therapeutic effectsImproved cognitive performance and mental alertness.PharmacokineticsAbsorption: Unknown.Distribution: Unknown.Metabolism and Excretion: Unknown.Half-life: Unknown.Time/action profile | ROUTE | ONSET | PEAK | DURATION |
|---|
| PO | Unknown | Unknown | Unknown |
Contraindications/PrecautionsContraindicated in: Allergy/hypersensitivity; Pregnancy and lactation (doses >200 mg/day due to caffeine content ).Use Cautiously in: Patients with caffeine sensitivity. Long term use of doses >250 mg/day may produce tolerance, psychological dependence, tachyarrhythmias, and sleep disturbances; Iron deficiency anemia (may worsen); Diabetes (may impair glucose control); Cardiac conditions (may induce arrhythmias in sensitive individuals); Bleeding disorders.Adverse Reactions/Side EffectsCardiovascularCentral nervous system- agitation
- dizziness
- excitement
- insomnia
- tremors
Gastrointestinal- nausea
- vomiting
- diarrhea
- hepatotoxicity
- abdominal pain
Fluid and ElectrolyteEndocrinologicHematologicInteractionsGreen tea may ↓ effects of adenosine.↑ risk of bleeding with anticoagulants or antiplatelet agents.↑ effects of CNS stimulants.May impair glucose control from antidiabetic agents.abrupt withdrawal can ↑ lithium levels.May ↓ dipyridamole —induced vasodilation.verapamil can ↑ caffeine concentrations by 25%.additive effects with methylxanthines.↑ risk of adverse cardiovascular effects with bitter orange.↑ risk of hepatotoxicity with hepatotoxic herbs or supplements.↑ risk of seizures, hypertension or stroke with ephedra and creatine.Oral (Adults) Range: 1–10 cups/day. One cup provides approximately 60 mg of caffeine.AvailabilityTea leaves: Nursing implicationsNursing assessment- Monitor BP and heart rate periodically during therapy.
- Lab Test Considerations: Monitor serum glucose, homocysteine and uric acid levels periodically during therapy.
- Monitor liver and kidney function periodically during therapy.
Potential Nursing DiagnosesImpaired memory (Indications)
Implementation- May be taken as tea or as an extract in capsules.
Patient/Family Teaching- Advise women who may be pregnant or who are breastfeeding to limit green tea due to the caffeine content.
Evaluation/Desired OutcomesCamellia sinensis
Related to Camellia sinensis: Camellia japonicaSynonyms for Camellia sinensisnoun a tropical evergreen shrub or small tree extensively cultivated in e.g. China and Japan and IndiaSynonymsRelated Words- tea leaf
- tea
- genus Camellia
- bush
- shrub
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