delta-9-tetrahydrocannabinol


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dronabinol

(droe-nab-i-nol) ,

delta-9-tetrahydrocannabinol

(trade name),

THC

(trade name),

Marinol

(trade name)

Classification

Therapeutic: antiemetics
Pharmacologic: cannabinoids
Pregnancy Category: C

Indications

Prevention of serious nausea and vomiting from cancer chemotherapy when other more conventional agents have failed.Management of anorexia associated with weight loss in patients with AIDS.

Action

Active ingredient in marijuana.
Has a wide variety of CNS effects, including inhibition of the vomiting control mechanism in the medulla oblongata.

Therapeutic effects

Suppression of nausea and vomiting.
Increased appetite in patients with AIDS.

Pharmacokinetics

Absorption: Extensively metabolized following absorption, resulting in poor bioavailability (10–20%).
Distribution: Enters breast milk in high concentrations. Highly lipid-soluble. Persists in tissues for prolonged period of time.
Protein Binding: 97%.
Metabolism and Excretion: Extensively metabolized; 50% excreted via biliary elimination. At least one metabolite is psychoactive.
Half-life: 25–36 hr.

Time/action profile (antiemetic effect)

ROUTEONSETPEAKDURATION
POunknown2–4 hr4–6 hr†
†Appetite stimulation lasts 24 hr or longer

Contraindications/Precautions

Contraindicated in: Hypersensitivity to dronabinol, marijuana, or sesame oil; Nausea and vomiting due to any other causes; Lactation: Lactation.
Use Cautiously in: Patients with history of substance abuse; Cardiovascular disease (due to potential adverse effects); Mania, depression, or schizophrenia (use may worsen these conditions); Patients taking sedatives, hypnotics, or other psychoactive drugs (increased risk of adverse effects); Geriatric: ↑ risk of adverse effects; Obstetric / Pediatric: Safety and efficacy not established.

Adverse Reactions/Side Effects

Central nervous system

  • anxiety (most frequent)
  • concentration difficulty (most frequent)
  • confusion (most frequent)
  • dizziness (most frequent)
  • drowsiness (most frequent)
  • mood change (most frequent)
  • abnormal thinking
  • depression
  • disorientation
  • hallucinations
  • headache
  • impaired judgment
  • memory lapse
  • paranoia

Ear, Eye, Nose, Throat

  • dry mouth (most frequent)

Cardiovascular

  • palpitations
  • syncope
  • tachycardia

Gastrointestinal

  • abdominal pain
  • nausea
  • vomiting

Dermatologic

  • facial flushing

Neurologic

  • ataxia
  • paresthesia

Miscellaneous

  • physical dependence
  • psychological dependence (high doses or prolonged therapy)

Interactions

Drug-Drug interaction

Additive CNS depression with alcohol, antihistamines,barbiturates, benzodiazepines, atropine, scopolamine,lithium, buspirone, muscle relaxants, opioid analgesics, tricyclicantidepressants, and sedative/hypnotics.Increased risk of tachycardia with amphetamine, atropine, scopolamine, cocaine, sympathomimetics, antihistamines, and tricyclicantidepressants.May increase blood levels of theophylline.Increased risk of tachycardia with caffeine -containing herbs (cola nut, guarana, mate, tea, coffee).Concomitant use of kava, valerian, skullcap, chamomile, or hopscan increase CNS depression.

Route/Dosage

Oral (Adults) Antiemetic—5 mg/m2 1–3 hr prior to chemotherapy; may repeat every 2–4 hr after chemotherapy to a total of 4–6 doses/day. If 5 mg/m2 dose is ineffective and no significant adverse reactions have occurred, dosage may be increased by 2.5 mg/m2 to a maximum of 15 mg/m2/dose. Appetite stimulant—2.5 mg twice daily initially; may be gradually increased as needed (up to 20 mg/day). Reduce dose to 2.5 mg/day in the evening or at bedtime if unable to tolerate 5 mg/day dose.

Availability (generic available)

Gelatin capsules: 2.5 mg, 5 mg, 10 mg

Nursing implications

Nursing assessment

  • Assess nausea, vomiting, appetite, bowel sounds, and abdominal pain prior to and following the administration of this drug.
  • Monitor hydration, nutritional status, and intake and output. Patients with severe nausea and vomiting may require IV fluids in addition to antiemetics.
  • Monitor BP and heart rate periodically throughout therapy.
  • Patients on dronabinol therapy should be monitored closely for side effects because the effects of dronabinol vary with each patient.

Potential Nursing Diagnoses

Risk for deficient fluid volume (Indications)
Imbalanced nutrition: less than body requirements (Indications)
Risk for injury (Side Effects)

Implementation

  • Dronabinol capsules should be refrigerated (not frozen).
    • Physical or psychological dependence may occur with high doses or prolonged therapy, causing a withdrawal syndrome (irritability, restlessness, insomnia, hot flashes, sweating, rhinorrhea, loose stools, hiccups, anorexia) when discontinued. This is unlikely to occur with therapeutic doses and short-term use of dronabinol.
  • Antiemetic: This drug may be administered prophylactically 1–3 hr prior to chemotherapy and repeated every 2–4 hr after chemotherapy up to 4–6 doses daily. Most patients respond to 5 mg three or four times daily.
  • Appetite Stimulant: Give 2.5 mg twice daily before lunch and supper initially. Reduce dose to 2.5 mg/day in the evening or at bedtime for patients unable to tolerate 5 mg/day dose. May increase dose to 2.5 mg at lunch and 5 mg before supper or 5 mg at lunch and 5 mg after supper if further therapeutic effect is desired and adverse effects are minimal. Most patients respond to 2.5 mg twice daily dose, but up to 10 mg bid have been tolerated in about 50% of patients. Adverse effects are dose related.

Patient/Family Teaching

  • Instruct patient to take dronabinol exactly as directed. Take missed doses as soon as possible but not if almost time for next dose; do not double doses. Signs of overdose (mood changes, confusion, hallucinations, depression, nervousness, fast or pounding heartbeat) may occur with increased doses.
  • Advise patient to call for assistance when ambulating, because this drug may cause dizziness, drowsiness, and impaired judgment and coordination. Avoid driving or other activities requiring alertness until response to the drug is known.
  • Instruct patient to change positions slowly to minimize orthostatic hypotension.
  • Caution patient to avoid taking alcohol or other CNS depressants during dronabinol therapy.
  • Advise patient and family to use general measures to decrease nausea (begin with sips of liquids and small, nongreasy meals; provide oral hygiene; remove noxious stimuli from environment).

Evaluation/Desired Outcomes

  • Prevention of and decrease in nausea and vomiting associated with chemotherapy.
  • Increased or maintained weight in patients with AIDS.
References in periodicals archive ?
The authors noted that these metabolites are known to be more water soluble and polar than delta-9-tetrahydrocannabinol itself, which may make it more difficult for them to enter the breast milk compartment.
"The long-term neurobehavioral effect of exposure to delta-9-tetrahydrocannabinol on the developing brain is unclear," the authors write.
The cannabis plant contains over seventy "phytocannabinoids." (35) The two most common psychoactive elements are Delta-9-Tetrahydrocannabinol ("THC") and cannabidiol ("CBD").
The cannabinoid drugs used were: delta-9-tetrahydrocannabinol (THC) (11 studies), THC + cannabidiol (two studies), cannabidiol (one study), dronabinol (five studies), nabilone (11 studies), levonantradol (two studies), GW842166 (one study), and dexabinol (one study).
SCPs have similar psychoactive effects to delta-9-tetrahydrocannabinol (A-9-THC), which is the psychoactive compound in natural cannabis (marijuana); however, the structure of the molecule is completely different.
Medicinal applications of delta-9-tetrahydrocannabinol and marijuana.
(c) MDA, 3,4 methylenedioxyamphetamine; MDMA, 3,4 methylenedioxymethamphetamine; MDEA, 3,4 methylene-dioxyethylamphetamine; MBDB, benzodioxolyl-N-methylbutanamine; THC, delta-9-tetrahydrocannabinol; 11-OH-THC, 11-hydroxy-delta-9-tetrahydrocannabinol.
Marijuana is known to contain at least 60 chemical products, but the main biological effects of marijuana result from delta-9-tetrahydrocannabinol (THC) and other cannabinoids, with cannabinoid JWH-018 being the active ingredient [3].
Also, the National Roadside Survey might have overestimated the proportion of impaired drivers because it tested for marijuana's psychoactive substances, delta-9-tetrahydrocannabinol (THC) and 11-hydroxy-delta-9-tetrahydrocannabinol, in oral fluids and blood levels.
That's the conclusion of laboratory research reported online July 7, 2014 in the Journal of Alzheimer's Disease that found that in cellular experiments, extremely low doses of the marijuana compound delta-9-tetrahydrocannabinol, or THC, curtailed the production of toxic beta-amyloid proteins and reduced their tendency to form sticky clumps in the brain.
The Miracle Fund will not pursue any companies or innovations using Delta-9-tetrahydrocannabinol (THC), the psycho-active Phytocannabinoid found in cannabis that stimulates cannabinoid receptors in the brain that gets people "high." Instead, the Miracle Fund will pursue only companies creating products and services that are safe, and legal.