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Cannabis

What is it?

Cannabis is an herbal medicine used to treat nausea and vomiting caused by cancer chemotherapy medicine. It is also used to decrease eye pressure, decrease pain, and to improve the appetite. Other uses for cannabis may include headaches, anxiety, asthma, Tourette syndrome, and to relax muscles.

Other names for cannabis include: Cannabis sativa, Hashish, Hemp, and Marijuana.

Ask your doctor, nurse, or pharmacist if you need more information about this medicine or if any information in this leaflet concerns you.

Before Using:

Tell your doctor if you .

  • are taking medicine or are allergic to any medicine (prescription or over-the-counter (OTC) or dietary supplement)
  • are pregnant or plan to become pregnant while using this medicine
  • are breastfeeding
  • have liver disease, history of mental illness, or a seizure disorder
  • have any other health problems, such as high blood pressure or heart or blood vessel disease

Dosage:

Talk with your caregiver about how much cannabis you should take. The amount depends on the strength of the medicine and the reason you are taking cannabis. If you are using this medicine without instructions from your caregiver, follow the directions on the medicine bottle. Do not take more medicine or take it more often than the directions tell you to.

  • Cannabis is a controlled substance and an illegal street drug in most areas. Ask your doctor for the correct dose.

To store this medicine:

Keep all medicine locked up and away from children. Store medicine away from heat and direct light. Do not store your medicine in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down and not work the way it should work. Throw away medicine that is out of date or that you do not need. Never share your medicine with others.

Drug and Food Interactions:

Do not take Cannabis without talking to your doctor first if you are taking:

  • Antiviral medicine for HIV and AIDS (protease inhibitors, examples: amprenavir (Agenerase(R)), indinavir (Crixivan(R)), nelfinavir (Viracept(R)), ritonavir (Norvir(R)), saquinavir (Invirase(R))) (22-27)
  • Cocaine (16,17)
  • Disulfiram (Antabuse(R)) (2)
  • Medicine for depression (examples: amitriptyline (Amitril(R), Elavil(R)); clomipramine (Anafranil(R)); citalopram (Celexa(R)); desipramine (Norpramin(R)); doxepin (Sinequan(R)); fluvoxamine (Luvox(R)); imipramine (Tofranil(R)); nortriptyline (Aventyl(R), Pamelor(R)); paroxetine (Paxil(R)); protriptyline (Vivactil(R)); trimipramine (Surmontil(R)); sertraline (Zoloft(R))) (1,29,30,40,41)
  • Medicine used for sleep, headache, seizures, or muscle relaxants (examples: amobarbital (Amytal (R)); aprobarbital (Alurate(R)); butabarbital (Butalan(R)); butalbital (Amaphen(R), Esgic(R), Fioricet(R), Fiorinal(R), Fiortal(R), Phrenilin(R), Sedapap(R)); fluoxetine (Prozac(R)); mephobarbital (Mebaral(R)); methohexital (Brevital(R) Sodium); pentobarbital (Nembutal(R)); phenobarbital (Barbita(R), Luminal(R)); secobarbital (Seconal(R)); thiopental (Pentothal(R) Sodium))) (3)
  • Sildenafil (Viagra(R)) (15)
  • Theophylline (Quibron-T(R), Theobid(R), Uniphyl(R)) (39)
  • Blood thinning medicines (example: warfarin (Coumadin(R)) (42)

Warnings:

  • Before taking cannabis, tell your doctor if you are pregnant or breastfeeding
  • Cannabis should be carefully used if you have abused drugs or have a history of mental illness
  • Cannabis should be carefully used if you have heart or blood vessel disease
  • Older people taking cannabis may be more likely to have mood changes than younger people
  • You should not drive, operate machinery, or take part in any activity that may cause you to be harmed if you use cannabis
  • Non-pharmaceutical cannabis may be contaminated with the fungus Aspergillus, which can be harmful to people with immune system problems
  • Do not drink alcohol and use cannabis

Side Effects:

Call your doctor right away if you have any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hand, swelling or tingling in your mouth or throat, chest tightness, trouble breathing, or rash.
  • Change in mood, depression, or hallucinations (seeing things that are not really there) (34-36)
  • Irregular heartbeat (31-33)
  • Blood in your vomit, nosebleed, or unusual bleeding (42)

Other Side Effects:

You may have the following side effects, but this medicine may also cause other side effects. Tell your doctor if you have side effects that you think are caused by this medicine.

  • Blurred vision, dizziness, drowsiness and sleepiness, loss of coordination (34,37,38)

References:

1. Benowitz NL & Jones RT:Effects of delta-9-tetrahydrocannabinol on drug distribution and metabolism. Clin Pharmacol Ther 1977; 22:259-268.

2. Lacoursiere RB & Swateck R:Adverse interaction between disulfiram and marijuana. Am J Psychiatry 1983; 140:243-244.

3. Product Information: Norvir(TM), ritonavir. Abbott Laboratories, Chicago, IL; 1996.

4. Riggs CE, Egorin MJ, Fuks JZ et al: Initial observations on the effects of delta-9-tetrahydrocannabinol on the plasma pharmacokinetics of cyclophosphamide and doxorubicin. J Clin Pharmacol 1981; 21:90S-98S.

5. Anon: Drug Facts and Comparisons. Facts and Comparisons Inc, St Louis, MO; 2000.

6. Product Information: Marinol(R), dronabinol. Roxane Laboratories, Columbus, OH; 1999.

7. Gralla RJ & Tyson LB: Delta-9-tetrahydrocannabinol as an antiemetic. In: Harvey DJ: Marijuana '84. Proceedings of the Oxford Symposium on Cannabis. IRL Press Ltd, Oxford, England; 1985.

8. Evans FJ: Cannabinoids: The separation of central from peripheral effects on a structural basis. Planta Med 1991; 57(Suppl-1):S60-S67.

9. Regelson W, Butler JR, Schulz J et al: Delta-9-tetrahydrocannabinol as an effective antidepressant and appetite-stimulating agent in advanced cancer patients. In: Braude MC & Szara S (eds): The Pharmacology of Marihuana. Raven Press, New York, NY; 1976

10. Herman TS, Einhorn LE, Jones SE et al:Superiority of nabilone over prochlorperazine as an antiemetic in patients receiving cancer chemotherapy. N Engl J Med 1979; 300:1295-1297.

11. Mathew RJ, Wilson WH, Humphreys DF et al:Middle cerebral artery velocity during upright posture after marijuana smoking. Acta Psychiatr Scand 1992; 86:173-178.

12. Herman TS, Einhorn LE, Jones SE et al:Superiority of nabilone over prochlorperazine as an antiemetic in patients receiving cancer chemotherapy. N Engl J Med 1979; 300:1295-1297.

13. Sillers K: Fungal infections and marihuana. Pharm Alert 1981; 12:3-4.

15. McLeod AL, McKenna CJ & Northridge DB: Myocardial infarction following the combined recreational use of Viagra® and cannabis. Clin Cardiol 2002; 25:133-134.

16. Foltin RW, Fischman MW, Pedroso JJ et al: Marijuana and cocaine interactions in humans: cardiovascular consequences. Pharmacol Biochem Behav 1987; 28:459-464.

17. Lukas SE, Sholar M, Kouri E et al: Marihuana smoking increases plasma cocaine levels and subjective reports of euphoria in male volunteers. Pharmacol Biochem Behav 1994; 48:715-721.

18. Lukas SE & Oroczo S: Ethanol increases plasma delta-9-tetrahydrocannabinol (THC) levels and subjective effects after marijuana smoking in human volunteers. Drug Alcohol Depend 2001; 64(2):143-149.

19. National Highway Traffic Safety Administration: Marijuana and alcohol combined severely impede driving performance. Ann Emerg Med 2000; 35(4):398-399.

20. Wright KA & Terry P: Modulation of the effects of alcohol on driving-related psychomotor skills by chronic exposure to cannabis. Psychopharmacology 2002; 160:213-219.

22. Chang AE, Shiling DJ, Stillman RC et al: Delta-9-tetrahydrocannabinol as an antiemetic for patients receiving cancer chemotherapy. Ann Intern Med 1979; 91:825-830.

23. Cone EJ & Huestis MA: Relating blood concentrations of tetrahydrocannabinol and metabolites to pharmacologic effects and time of marijuana usage. Ther Drug Monitor 1993; 15:527-532.

24. Frytak S, Moertel CG, O'Fallon J et al: Delta-9-tetrahydrocannabinol as an antiemetic in patients treated with cancer chemotherapy: a double comparison with prochlorperazine and a placebo. Ann Intern Med 1979; 91:825-830.

25. Kosel BW, Aweeka FT, Benowitz NL et al: The effects of cannabinoids on the pharmacokinetics of indinavir and nelfinavir. AIDS 2002; 16(4):543-550.

26. Ohlsson A, Lindgren JE, Wahlen A et al: Plasma delta-9-tetrahydrocannabinol concentrations and clinical effects after oral and intravenous administration and smoking. Clin Pharmacol Ther 1980; 28:409-415.

27. Product Information: Norvir(TM), ritonavir. Abbott Laboratories, Chicago, IL, 1996.

28. Zanoli P, Avallone R & Baraldi M: Sedative and hypothermic effects induced by beta-asarone, a main component of Acorus calamus. Phytother Res 1998; 12(Supp 1):S114-S116.29.

29. Stoll AL, Cole JO & Lukas SE: A case of mania as a result of fluoxetine-marijuana interaction. J Clin Psychiatry 1991; 52(6): 280-281.

30. Wilens TE, Biederman J & Spencer TJ: Case study: Adverse effects of smoking marijuana while receiving tricyclic antidepressants. J Am Acad Child Adolesc Psychiatry 1997; 36(1):45-48.

31. Hollister LE: THC as a sedative, hypnotic and muscle relaxant. In: Harvey (ed): Marihuana '84, Proceedings of the Oxford Symposium on Cannabis. IRL Press Ltd, Oxford, England, 1985.

32. Noyes R Jr, Brunk SF, Baram DA et al: Analgesic effects of delta-9- tetrahydrocannabinol. In: Braude MC & Szara S: The Pharmacology of Marihuana. Raven Press, New York, NY, 1976.

33. Vachon L, Mikus P, Morrissey W et al: Bronchial effect of marihuana smoke in asthma. In: Braude MC & Szara S (eds): The Pharmacology of Marihuana. Raven Press, New York, NY, 1976.

34. Product Information: Marinol(R), dronabinol. Roxane Laboratories, Columbus, OH, 1999.

35. Patton GC, Coffey C, Carlin J et al: Cannabis use and mental health in young people: cohort study. BMJ 2002; 325(11):1195-1198.

36. Szymanski HV: Prolonged depersonalization after marijuana use. Am J Psychiatry.1981 Feb;138(2):231-3.

37. Herman TS, Einhorn LE, Jones SE et al: Superiority of nabilone over prochlorperazine as an antiemetic in patients receiving cancer chemotherapy. N Engl J Med 1979; 300:1295-1297.

38. Mathew RJ, Wilson WH, Humphreys DF et al: Middle cerebral artery velocity during upright posture after marijuana smoking. Acta Psychiatr Scand 1992; 86:173-178.

39. Jusko WJ, Gardner MJ, Mangione A et al: Factors affecting theophylline clearances: age, tobacco, marijuana, cirrhosis, congestive heart failure, obesity, oral contraceptives, benzodiazepines, barbiturates and ethanol. J Pharm Sci 1979; 68:1358-1366.

40. Hansten PD: Marijuana interactions. Drug Interactions Newsletter. Applied Therapeutics, Inc, Spokane, WA, 1984; 4:5-7, 85.

41. Hillard JR & Vieweg WV: Marked sinus tachycardia resulting from the synergistic effects of marijuana and nortriptyline. Am J Psychiatry 1983; 140:626-627.

42. Yamreudeewong W, Wong HK, Brausch LM, et al: Probable interaction between warfarin and marijuana smoking. Ann Pharmacother 2009; 43(7):1347-1353.


Last Updated: 11/4/2014

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