Antiparasitics, Complementary and Alternative Medicines - Pharm

______ nfections are extremely common in many parts of the world -warm moist climate, poor sanitation where insects and other vectors of disease are prevalent.

Endoparasitic

What are caused by organisms that live on the skin or hair shafts of patients. The most common are the lice and mites that cause pediculosis and scabies.

ectoparasitic infestations

What does this refer to

“Amebiasis, balantidiasis, cryptosporidiosis, giardiasis, and trichomoniasis”

infections caused by protozoan parasites that dwell in the lumen and tissues of their human hosts.

What does this refer to

__________ is a nitroimidazole compound; well absorbed po and is widely distributed to tissues and fluids throughout the body, including the liver and CNS.

• Extensively metabolized before undergoing renal excretion.

• usually po; IV available in severe infections.

• active against several anaerobic protozoa that commonly cause infection: Entamoeba histolytica (the agent of amebiasis); Giardia intestinalis (G. lamblia); Trichomonas vaginalis (trichomoniasis); and Balantidium coli (balantidiasis).

• active against anaerobic bacteria, including Bacteroides fragilis, Helicobacter pylori, and Clostridium difficile

• the drug of choice for amebiasis, giardiasis, and trichomoniasis

Metronidazole (Flagyl)

What causes abdominal discomfort and diarrhea in persons infected with the cyst form of Giardia. In the western US, Giardia cysts are sometimes present in contaminated streams and ponds and are ingested by campers. Metronidazole for 5 days usual.

Giardiasis

What is a STD that produces vaginitis in women but is usually asymptomatic in men. To prevent reinfection, it is important to treat patients and their sexual partners. Treatment can consist either of a single large dose of metronidazole or of smaller doses taken over a 7-day period.

Trichomoniasis

What has activity against C. difficile but is no longer considered first-line. It is occasionally used to treat infections caused by other anaerobic bacteria.

• Typically used for intra-abdominal or GU infections

Metronidazole

What does this refer to

__________- usually well tolerated, but can cause GI discomfort.

• Other adverse effects: nausea, vomiting, a metallic taste, and transient leukopenia or thrombocytopenia. Take with food.

• has been shown to be mutagenic in bacteria and mammalian cell cultures.

• Prudent to avoid prescribing the drug to women during their first trimester of pregnancy whenever possible.

Metronidazole

What can cause disulfiram- like reaction with ethanol, so patients should avoid drinking alcohol while they are undergoing treatment

Metronidazole

What can cause adverse reactions/drug interactions of

• nausea/vomiting,

• xerostomia (dry mouth)

• dysgeusia (usually manifest as a metallic taste)

• anorexia and abdominal pain

• Drug interaction

  • Avoid alcohol during treatment with and for 3 days after discontinuation of therapy. Co-administration may cause a disulfiram like reaction which causes symptoms such as nausea, vomiting, headache, flushing, and abdominal cramps. Note: some medications may also contain alcohol and should be avoided.

Metronidazole

What is a second-generation nitroimidazole similar to metronidazole but active against metronidazole-resistant strains of Trichomonas vaginalis.

• can cause anorexia, nausea, and vomiting, as well as a bitter taste in the mouth, and it is contraindicated in the first trimester of pregnancy.

tinidazole

What does this refer to

“one of the most common infectious diseases in the world today, is believed to be responsible for more deaths than any other infectious disease.”

• Caused by 4 species Plasmodium falciparum, P. malariae, P. ovale, and P. vivax.

• Most cases are caused by by P. falciparum or P. vivax

• has largely been eliminated from industrialized countries in temperate regions, so most infections that are diagnosed in people residing in the United States are infections that were acquired during travel in other countries. Nevertheless, periodic outbreaks of mosquito-borne malaria still occur in the United States.

Malaria

What drugs are used for malaria

Chloroquine, Quinine, and Quinidine

What is this referring to

“________, a drug that had been used for centuries to treat malaria, was supplanted by chloroquine after World War II. Until the 1980s, when resistance to chloroquine became widespread, chloroquine remained the drug of choice. Now that drug resistance has severely curtailed the effectiveness of chloroquine, quinine is once again being used to treat malaria in many regions of the world”

Quinine

What does this refer to

• The only areas where most P. falciparum organisms are sensitive to _________ are the Caribbean islands, the part of Central America that is west of the Panama Canal, and parts of North and West Africa and the Middle East. In these __________-sensitive areas, _______ is still the drug of choice for both the prevention and the treatment of all types of malaria, although it must be used in combination with primaquine to eradicate vivax or ovale malaria

• Adverse effects of __________ are GI distress, nausea, and vomiting. Toxic doses can cause retinal damage and even blindness. In pregnant women, chloroquine should be used cautiously because fetal damage has been reported.

• Patients with _________-resistant malaria are usually treated with a combination of quinine sulfate plus either doxycycline or pyrimethamine-sulfadoxine. Alternatives include atovaquone-proguanil (Malarone) and artesunate plus mefloquine (Lariam).

Chloroquine

What does this refer to

• ______ is an antimalarial drug that is used for both the prevention and treatment of chloroquine-resistant malaria

• ________ can cause a severe neuropsychiatric syndrome characterized by hallucinations, anxiety, confusion, seizures, and coma. It can also cause leukopenia and thrombocytopenia.

• For patients who cannot tolerate ________, doxycycline can be used to prevent malaria in areas of chloroquine-resistance

Mefloquine (Lariam)

__________ is a biguanide derivative that acts as a folate reductase inhibitor. Sometimes combined with atovaquone to treat chloroquine-resistant malaria, it is available as a fixed-dose combination product. (Malarone)

Proguanil (chloroguanide)

What does this refer to

• ________, has traditionally been classified as a protozoan parasite or actually a fungus.

• Causing pneumonia in premature and malnourished infants, the organism causes pneumonia and other diseases in immunocompromised persons, including those with AIDS.

Pneumocystis jiroveci

What does this refer to

• Trimethoprim-sulfamethoxazole (Bactrim DS)

• Alternatives = Atovaquone , and pentamidine

Treatment for Pneumocystis jiroveci (carinii)

• __________ usually act either by inhibiting metabolism in the parasite (as occurs when a benzimidazole drug is used) or by causing muscle paralysis of the parasite (as occurs when ivermectin, praziquantel, or pyrantel is used).

• ______ kill the parasites without harming host cells, but the molecular basis for their selective toxicity is unclear. In many cases, a single dose or a few doses are curative.

Anthelmintic drugs

_______ are primarily used to treat intestinal nematode infections, including ascariasis, capillariasis, hookworm infection, pinworm infection, and whipworm infection

• Side effects - mild GI discomfort and constipation or diarrhea.

• High doses causes hepatitis or hematologic toxicity.

• contraindicated during pregnancy because of their potential to inhibit mitosis and impair fetal development.

Albendazole (Albenza) and mebendazole (Vermox)

• ________ is a pyrimidine derivative.

• activates nicotinic acetylcholine receptors in somatic muscles of nematodes and causes depolarizing neuromuscular blockade.

• A liquid suspension for children and adults who have ascariasis, hookworm infection, or pinworm infection.

• The drug is poorly absorbed from the gut and acts primarily within the intestinal tract.

• It is usually well tolerated, but it can cause abdominal cramps, anorexia, diarrhea, and vomiting.

Pyrantel (Pin-X)

What is used together with conventional medicine

Complementary

What is used in place of conventional medicine

Alternative

What does this refer to

• Products that contain a “dietary ingredient” and are intended to add to or supplement the diet

  • Does NOT include tobacco

• Can occur in many dosage forms (e.g. tablets, capsules, gelcaps, liquids, powder, etc.)

• NOT regulated by FDA as “conventional” drug products

  • Manufacturers are not required to follow Good Manufacturing Practices

  • Manufacturers do have the burden of proof for safety

  • No pre-marketing approval or specific post-market surveillance period

  • Federal Trade Commission regulates claims of efficacy or truth in advertising

• FDA only takes action against unsafe supplements AFTER they reach the market

Dietary Supplements

• Claims can be used on food and dietary supplement labels about:

• Structure / Function

  • Describe the role of a nutrient or dietary ingredient intended to affect the normal structure or function of the human body

• Nutrient Content Claims

  • Characterize the relative amount of nutrient or dietary substance in the product

  • Make an accurate quantitative statement that does not otherwise “characterize”

Dietary Supplement Health and Education Act (1994) (DSHEA)

What does this refer to

• Common Uses

  • Treatment and prevention of upper respiratory infections and common cold in adults

  • Wound healing, boils, abscesses, eczema, psoriasis, bee stings (topically)

• Mechanism of Action (proposed)

  • Increases phagocytosis and lymphocyte activity possibly by stimulating the release of TNF, IL-1, and interferon

• Safety

  • Generally considered safe for short-term use (up to 12 weeks)

• Adverse Effects

  • Usually well tolerated

  • Low incidence of GI side effects

  • Allergic reaction more common in people with allergies to Asteraceae/Compositae plant family

    • e.g. ragweed, chrysanthemims, daisies, marigolds

• Drug/Food Interactions

  • Immnosuppressants—decreased effects

  • Drugs metabolized by CYP3A4

    • Seen in laboratory tests

    • Has both inhibited and induced the enzymes

    • Mild effects

Echinacea

What does this refer to

• Common Uses

  • As an “adaptogen”—increases resistance to environmental stress

    • Antioxidant

  • As a general “tonic”

    • To improve well being and increases resistance to various disease states

      • Anemia, DM, insomnia, concentration, URI

• Safety

  • Possibly safe for short-term use

  • Generally considered safe

• Adverse Effects

  • GI, CNS, CV effects similar to placebo

  • Panax ginseng may cause more insomnia

• Interactions

  • Oral hypoglycemics = enhanced effects

  • Bleeding risk with anticoagulants

Ginseng

What does this refer to

• Common Uses

  • Intermittent Claudication

  • Dementia/Alzheimer’s Disease

  • Cerebral insufficiency

  • Asthma, bronchitis

  • Refractory Depression

  • Depression-induced sexual dysfunction

• Mechanism of Action

  • Contains flavoglycosides that have antioxidant activities

  • May inhibit platelet-activating factor

  • May stimulate endothelial releasing factor and prostacyclin

• Safety

  • Theoretically contraindicated in active bleeding

  • UNCOOKED seeds and pulp are neurotoxic if ingested

    • Leaf extracts are likely safe

    • Pulp can cause poison-ivy like dermatitis

• Adverse Effects

  • Headache

  • Nausea, diarrhea, dyspepsia

  • Allergic skin reactions

Ginko

What does this refer

• Common Uses

  • High cholesterol, HTN, immune support, and antibacterial/antifungal

• Mechanism of Action

  • Alliin, the sulfur-containing amino acid derivative found in garlic, and allicin are responsible for activity

    • Avoid odorless preparations (alliin is destroyed)

• Safety

  • Theoretically contraindicated in patients with active bleeding

  • Allergic reactions are potential with cross-reactivity to lily family (i.e. onions)

• Adverse Effects

  • Breath and body odor

  • Heartburn, GI upset

Garlic

What does this refer

• Common Uses

  • Mild to moderate knee osteoarthritis, generalized osteoarthritis, rheumatoid arthritis

• Mechanism of Action

  • Stimulates metabolism of chondrocytes and synoiocytes

  • Involved in the synthesis of cartilage components

  • May inhibit cytokine-stimulated production of inflammatory mediators

• Safety

  • Theoretically worsens diabetes—use with caution

  • May cause allergic reaction to those with shellfish allergy

• Adverse Effects

  • Mild GI discomfort

  • heartburn

  • diarrhea

Glucoasmine

What does this refer to

• Common Uses

  • Osteoarthritis, ophthalmologic uses, coronary artery disease, interstitial cystitis, psoriasis, enhancement of iron absorption

• Mechanism of Action

  • Inhibits synovial enzymes that contribute to cartilage destruction

• Safety

  • May increase bleeding time with high doses

  • Caution with shark or bovine allergies (common sources for chondroitin)

• Adverse Effects

  • Mild GI complaints

  • nausea

  • diarrhea

Chondroitin

What does this refer to

• Common Uses

  • Osteoarthritis, cholesterol, depression

• Mechanism of Action

  • Turmeric contains curcumin which might reduce inflammation

• Safety

  • Stimulates the production of gastric acid

  • Increases the risk of bleeding

• Adverse Effects

  • GI complications

  • Hypoglycemia

Turmeric