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PHARMACOLOGY (sahrgeant) > ANTIPROTOZOAL > Flashcards

ANTIPROTOZOAL Flashcards

1
Q

What percentage of the world’s population is affected by amebiasis?

A

About 10%

Amebiasis causes invasive disease in about 50 million people and results in approximately 100,000 deaths annually.

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2
Q

Which species of Entamoeba requires treatment for amebiasis?

A

E. histolytica

E. histolytica is the third-leading cause of mortality by parasitic infection.

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3
Q

How is amebiasis primarily transmitted?

A

Fecal-oral route

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4
Q

What are the major clinical manifestations of E. histolytica infection?

A
  • Colitis
  • Bloody diarrhea (amebic dysentery)
  • Amebic liver abscess
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5
Q

What is the cornerstone therapy for amebiasis?

A

Metronidazole or its analogue tinidazole

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6
Q

What additional treatment is recommended for patients with amebic colitis or liver abscess?

A

A luminal agent in addition to metronidazole

Luminal agents include paromomycin and iodoquinol.

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7
Q

What is the causative agent of giardiasis?

A

Giardia intestinalis

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8
Q

Which populations are at higher risk for giardiasis transmission?

A
  • Children in day-care centers
  • Institutionalized individuals
  • Male homosexuals
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9
Q

What are the three syndromes associated with Giardia infection?

A
  • Asymptomatic carrier state
  • Acute self-limited diarrhea
  • Chronic diarrhea with malabsorption
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10
Q

What is the treatment of choice for giardiasis?

A

Metronidazole

Tinidazole may be superior, and paromomycin is safe for pregnant women.

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11
Q

What organism causes trichomoniasis?

A

Trichomonas vaginalis

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12
Q

What is the most common nonviral sexually transmitted disease?

A

Trichomoniasis

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13
Q

What is the main treatment for trichomoniasis?

A

Metronidazole

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14
Q

What is the primary host for Toxoplasma gondii?

A

Cats and other feline species

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15
Q

What are common routes of infection for toxoplasmosis in humans?

A
  • Ingestion of undercooked meat
  • Ingestion of contaminated vegetables
  • Direct contact with cat feces
  • Transplacental infection
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16
Q

What is a common clinical manifestation of congenital toxoplasmosis?

A

Chorioretinitis

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17
Q

What is the primary treatment for toxoplasmic encephalitis?

A

Pyrimethamine and sulfadiazine with folinic acid

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18
Q

What is the role of spiramycin in toxoplasmosis treatment?

A

Used to treat acute acquired toxoplasmosis in early pregnancy

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19
Q

What are the primary pathogens causing cryptosporidiosis?

A
  • Cryptosporidium parvum
  • Cryptosporidium hominis
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20
Q

How are Cryptosporidia transmitted?

A

Direct human-to-human contact or contaminated water supplies

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21
Q

What is the treatment for cryptosporidiosis in immunocompetent individuals?

A

Nitazoxanide

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22
Q

What is the most effective therapy for cryptosporidiosis in immunocompromised patients?

A

Restoration of immune function

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23
Q

What is trypanosomiasis commonly known as?

A

Sleeping sickness.

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24
Q

What organism causes trypanosomiasis?

A

Trypanosoma brucei.

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25
Q

How is trypanosomiasis transmitted?

A

By bloodsucking tsetse flies of the genus Glossina.

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26
Q

In which geographical area is trypanosomiasis primarily found?

A

Sub-Saharan Africa.

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27
Q

What are the two types of African trypanosomiasis?

A
  • East African (Rhodesian; T. brucei rhodesiense)
  • West African (Gambian; T. brucei gambiense)
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28
Q

What symptoms characterize early-stage trypanosomiasis?

A
  • Febrile illness
  • Lymphadenopathy
  • Splenomegaly
  • Occasional myocarditis
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29
Q

What is the standard therapy for early-stage T. brucei gambiense?

A

Pentamidine.

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30
Q

What is the standard therapy for early-stage T. brucei rhodesiense?

A

Suramin.

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31
Q

What is the treatment for late-stage trypanosomiasis?

A

Eflornithine.

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32
Q

What is NECT?

A

Nifurtimox-eflornithine combination therapy.

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33
Q

True or False: Eflornithine is effective against late-stage T. brucei rhodesiense.

A

False.

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34
Q

What is the estimated global prevalence of Chagas disease?

A

About 6-7 million.

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35
Q

What is the primary vector for Chagas disease?

A

Bloodsucking triatomid bugs.

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36
Q

What are the two drugs used to treat Chagas disease?

A
  • Nifurtimox
  • Benznidazole
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37
Q

What are the major complications of chronic Chagas disease?

A
  • Cardiomyopathy
  • Megaesophagus
  • Megacolon
  • Death
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38
Q

What type of disease is leishmaniasis?

A

Vector-borne zoonosis.

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39
Q

What is the primary reservoir for Leishmania?

A

Small mammals and canines.

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40
Q

What are the major syndromes of human leishmaniasis?

A
  • Cutaneous
  • Mucocutaneous
  • Diffuse cutaneous
  • Visceral (kala azar)
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41
Q

What is the main treatment for visceral leishmaniasis?

A

Liposomal amphotericin B.

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42
Q

What is the first orally active agent approved for leishmaniasis?

A

Miltefosine.

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43
Q

What is a significant limitation of miltefosine?

A

Its teratogenic effects limit its use in women of childbearing age.

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44
Q

Fill in the blank: The classic therapy for all species of Leishmania is with _______.

A

Pentavalent antimony compounds.

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45
Q

What is the geographical distribution of Chagas disease?

A

Primarily confined to Latin America.

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46
Q

True or False: Chagas disease can be transmitted by blood transfusion.

A

True.

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47
Q

What is Babesiosis?

A

A tick-borne zoonosis caused by Babesia microti or B. divergens that resembles malaria.

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48
Q

What are the symptoms of Babesiosis?

A

Febrile illness, hemolysis, and hemoglobinuria.

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49
Q

In which individuals can Babesiosis be severe or fatal?

A

In asplenic or severely immunocompromised individuals.

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50
Q

What is the therapy for severe Babesiosis?

A

Combination of clindamycin and quinine.

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51
Q

What therapy is used for mild or moderate Babesiosis?

A

Combination of azithromycin and atovaquone.

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52
Q

What is Balantidiasis?

A

An infection of the large intestine caused by Balantidium coli.

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53
Q

How does Balantidiasis differ from amebiasis?

A

Balantidiasis usually responds to tetracycline therapy.

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54
Q

What does Cyclospora cayetanensis cause in normal hosts?

A

Self-limited diarrhea.

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55
Q

What can Cyclospora cayetanensis cause in immunocompromised individuals?

A

Prolonged diarrhea.

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56
Q

What does Cystoisospora belli cause in patients with AIDS?

A

Diarrhea.

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57
Q

What is the treatment for Cyclospora and Cystoisospora infections?

A

Trimethoprim-sulfamethoxazole.

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58
Q

What are Microsporidia classified as?

A

Fungi.

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59
Q

What type of organisms are Microsporidia?

A

Spore-forming, unicellular, eukaryotic organisms.

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60
Q

What is Amphotericin B primarily used for?

A

Amphotericin B is a highly effective antileishmanial agent that cures >90% of cases of visceral leishmaniasis.

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61
Q

What types of leishmaniasis can Amphotericin B treat?

A

Amphotericin B is used for visceral, cutaneous, and mucosal leishmaniasis.

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62
Q

How does the lipid preparation of Amphotericin B affect its toxicity?

A

Lipid preparations of Amphotericin B have reduced toxicity.

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63
Q

What is Eflornithine’s mechanism of action?

A

Eflornithine is an irreversible catalytic (suicide) inhibitor of ornithine decarboxylase.

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64
Q

What is the role of polyamines in trypanosomes?

A

Polyamines (putrescine, spermidine, and spermine) are required for cell division and normal cell differentiation.

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65
Q

What distinguishes the susceptibility of Eflornithine between parasite and human enzymes?

A

Both enzymes are equally susceptible to inhibition, but the mammalian enzyme is turned over rapidly, while the parasite enzyme is stable.

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66
Q

How is Eflornithine administered?

A

Eflornithine is given by intravenous infusion.

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67
Q

What is the half-life of Eflornithine?

A

The half-life of Eflornithine is 3-4 hours.

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68
Q

What is the renal clearance rate of Eflornithine after IV administration?

A

The renal clearance rate is rapid at 2 mL/min/kg.

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69
Q

What is NECT and how does it compare to eflornithine alone?

A

NECT is a combination therapy that is safer and more efficacious than eflornithine alone for late-stage gambiense sleeping sickness.

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70
Q

What are the common adverse reactions associated with Eflornithine?

A

Adverse reactions include abdominal pain, headache, and reactions at injection sites.

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71
Q

What severe reactions can occur with Eflornithine alone?

A

Severe reactions include fever (6%), seizures (4%), and diarrhea (2%).

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72
Q

What is the case fatality rate for Eflornithine compared to melarsoprol?

A

The case fatality rate for Eflornithine is 0.7%-1.2%, while for melarsoprol it is 4.9%.

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73
Q

What are the therapeutic uses of Eflornithine?

A

Eflornithine is used for late-stage West African trypanosomiasis caused by T. brucei gambiense.

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74
Q

What is the dosing regimen for treating visceral leishmaniasis with Amphotericin B?

A

3 mg/kg intravenously on days 1-5, 14, and 21 for a total dose of 21 mg/kg.

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75
Q

What is the cure rate for Eflornithine when combined with nifurtimox (NECT)?

A

NECT achieves a higher cure rate of 96.5% compared to eflornithine alone at 91.5%.

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76
Q

Fill in the blank: Amphotericin B complexes with _______ in the cell membrane.

A

ergosterol precursors

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77
Q

True or False: Eflornithine binds to plasma proteins.

A

False

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78
Q

What is the primary biochemical effect of Eflornithine on trypanosomes?

A

Polyamine depletion.

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79
Q

What is melarsoprol used to treat?

A

Late (CNS) stages of East African trypanosomiasis caused by T. brucei rhodesiense

It is the only drug for this condition despite its risks.

80
Q

What is the first-line treatment for late-stage West African trypanosomiasis caused by T. brucei gambiense?

A

NECT

Melarsoprol is effective but NECT has become the preferred treatment.

81
Q

Which two halogenated 8-hydroxyquinolines are used as luminal agents?

A
  • Iodoquinol (diiodohydroxyquin)
  • Clioquinol (iodochlorhydroxyquin)

They are used to eliminate intestinal colonization with E. histolytica.

82
Q

What is the preferred luminal agent for amebiasis due to its superior adverse-event profile?

A

Paromomycin

It is preferred over iodoquinol and clioquinol.

83
Q

What is the most important toxic reaction associated with clioquinol?

A

Subacute myelo-optic neuropathy

This is a serious side effect primarily linked to clioquinol.

84
Q

What is the recommended dose of iodoquinol for adults?

A

650 mg orally three times daily for 20 days

For children, it is 30-40 mg/kg body weight orally, divided three times a day.

85
Q

What is the mechanism of action of melarsoprol?

A

Melarsoprol is metabolized to melarsen oxide, which inactivates many enzymes by reacting with vicinal sulfhydryl groups

It specifically binds to trypanothione, inhibiting trypanothione reductase.

86
Q

What is a major risk factor for developing encephalopathy when using melarsoprol?

A

High parasitemia

A febrile reaction often occurs soon after drug injection, especially if parasitemia is high.

87
Q

What is the dosing regimen for melarsoprol for both T. brucei gambiense and T. brucei rhodesiense?

A

2.2 mg/kg/d IV for 10 days

This dosing is critical for effective treatment.

88
Q

True or False: Melarsoprol can be administered outside of hospital supervision.

A

False

It should only be given under hospital supervision due to significant toxicity.

89
Q

What adverse effect can occur in patients treated with melarsoprol after a febrile episode?

A

Increased incidence of reactive encephalopathy

Initiating therapy during a febrile episode raises the risk of this serious complication.

90
Q

What is the active metabolite of melarsoprol?

A

Melarsen oxide

It is the form that exerts the therapeutic effect.

91
Q

What is a common side effect of iodoquinol in children with chronic diarrhea?

A

Optic atrophy and permanent vision loss

This is associated with high doses of iodoquinol.

92
Q

What is the half-life of the active metabolite of melarsoprol?

A

43 hours

This contributes to the drug’s prolonged action.

93
Q

Fill in the blank: Melarsoprol is always administered by _______.

A

slow intravenous injection

Care must be taken to avoid leakage into surrounding tissues.

94
Q

What should be monitored during melarsoprol treatment due to potential toxicity?

A

Renal and hepatic function

Albuminuria and other signs of renal or hepatic impairment are common.

95
Q

What is the mechanism of action of metronidazole?

A

Active against anaerobic protozoal parasites and anaerobic bacteria

Metronidazole is a prodrug requiring reductive activation by susceptible organisms.

96
Q

Which organisms are clinically effective against metronidazole?

A
  • Trichomoniasis
  • Amebiasis
  • Giardiasis

Other 5-nitroimidazoles include tinidazole, secnidazole, and ornidazole.

97
Q

What types of bacteria does metronidazole exhibit antibacterial activity against?

A
  • Anaerobic cocci
  • Anaerobic gram-negative bacilli (e.g., Bacteroides spp.)
  • Anaerobic spore-forming gram-positive bacilli (e.g., Clostridium)
  • Microaerophilic bacteria (e.g., Helicobacter, Campylobacter)

Nonsporulating gram-positive bacilli are often resistant.

98
Q

How does metronidazole get activated in anaerobic organisms?

A

Through reductive activation of the nitro group by electron transport components

This process forms a highly reactive nitro radical anion that kills susceptible organisms.

99
Q

What is the preferred treatment regimen for trichomoniasis using metronidazole?

A

2 g metronidazole as a single oral dose for both males and females

Treatment failures due to metronidazole-resistant strains are becoming more common.

100
Q

What is the recommended dose of metronidazole for amebiasis?

A

500-750 mg taken orally three times daily for 7-10 days

For children, 35-50 mg/kg/d in three divided doses for 7-10 days.

101
Q

What is the first-line therapy for giardiasis?

A

Tinidazole as a single 2-g dose

This is an appropriate first-line therapy.

102
Q

What is a common side effect of metronidazole?

A
  • Headache
  • Nausea
  • Dry mouth
  • Metallic taste

Other side effects include vomiting, diarrhea, and abdominal distress.

103
Q

True or False: Metronidazole can cause a disulfiram-like effect when alcohol is consumed.

A

True

This may result in abdominal distress, vomiting, flushing, or headache.

104
Q

What is the effect of increasing levels of oxygen on metronidazole’s activity?

A

Inhibits metronidazole-induced cytotoxicity

Oxygen competes with metronidazole for electrons, decreasing its activation.

105
Q

Fill in the blank: Metronidazole penetrates well into body tissues and fluids, including _______.

A

Vaginal secretions, seminal fluid, saliva, breast milk, and CSF

It is distributed to a volume approximating total body water.

106
Q

What are the principal metabolites of metronidazole?

A
  • Hydroxy metabolite (longer t1/2 ~12 h)
  • Glucuronides

The hydroxy metabolite has about 50% of the antitrichomonal activity of metronidazole.

107
Q

What should be done if a patient experiences numbness or paresthesias while on metronidazole?

A

Withdraw metronidazole

Reversal of serious sensory neuropathies may be slow or incomplete.

108
Q

What are some drug interactions associated with metronidazole?

A
  • Disulfiram (confusional states)
  • Warfarin (prolonged prothrombin time)
  • Lithium (CNS toxicity)

Metronidazole should not be used with disulfiram or any disulfiram-like drug.

109
Q

What is the elimination route for metronidazole after oral dosing?

A

More than 75% is eliminated in the urine

Mostly as metabolites formed by the liver.

110
Q

What conditions contraindicate the use of metronidazole?

A

Active disease of the CNS, severe hepatic disease, and first trimester of pregnancy

Caution is advised due to potential neurotoxicity.

111
Q

What type of compound is miltefosine?

A

An alkylphosphocholine analogue

Developed originally as an anticancer agent.

112
Q

What diseases is miltefosine highly curative against?

A

Visceral leishmaniasis and cutaneous forms of the disease.

113
Q

What is a major drawback of using miltefosine?

A

Its teratogenicity; must not be used in pregnant women.

114
Q

What is significant about miltefosine regarding leishmaniasis treatment?

A

It is the first orally available therapy for leishmaniasis.

115
Q

Is the mechanism of action of miltefosine understood?

A

No, it is not understood.

116
Q

What may miltefosine alter in its mechanism of action?

A

Ether-lipid metabolism, cell signaling, or glycosylphosphatidylinositol anchor biosynthesis.

117
Q

What type of transporter is involved in miltefosine’s action?

A

A P-type ATPase belonging to the aminophospholipid translocase subfamily.

118
Q

What leads to drug resistance in miltefosine?

A

A point mutation in the transporter that leads to decreased drug uptake.

119
Q

What are the two main drugs used to treat American trypanosomiasis?

A

Nifurtimox and benznidazole.

120
Q

What forms of T. cruzi do nifurtimox and benznidazole target?

A

Both the trypomastigote and amastigote forms.

121
Q

What is the activation mechanism for nifurtimox and benznidazole?

A

Activation by an NADH-dependent mitochondrial nitroreductase to nitro radical anions.

122
Q

What cellular damage is caused by the nitro anion radicals from nifurtimox and benznidazole?

A

Lipid peroxidation, membrane injury, and enzyme inactivation.

123
Q

What leads to drug resistance in nifurtimox and benznidazole?

A

Reduced nitroreductase expression.

124
Q

What are common side effects of nifurtimox and benznidazole?

A

Hypersensitivity reactions, nausea, vomiting, myalgia, and weakness.

125
Q

What is the most common adverse event for benznidazole?

A

Urticarial dermatitis.

126
Q

What should be monitored during benznidazole therapy?

A

Blood cell counts.

127
Q

What is the recommended dose of miltefosine for adults over 45 kg?

A

150 mg/kg/d for 28 days.

128
Q

What is the recommended dose of miltefosine for patients weighing 30-45 kg?

A

100 mg/kg/d.

129
Q

What is the half-life of nifurtimox?

130
Q

What is the half-life of benznidazole?

131
Q

What is the therapeutic range for benznidazole in adults?

132
Q

What should be avoided during treatment with nifurtimox?

A

Ingestion of alcohol.

133
Q

What is the recommended treatment duration for nifurtimox in acute infection?

134
Q

What is the recommended treatment duration for benznidazole?

135
Q

What is the recommended dose of benznidazole for adults?

A

5-7 mg/kg/d in two divided doses.

136
Q

What should be done if gastric upset occurs during benznidazole treatment?

A

Adjust the dosage.

137
Q

What is Nitazoxanide?

A

An oral synthetic broad-spectrum antiparasitic agent

Used for the treatment of cryptosporidiosis and giardiasis in adults and immunocompetent children.

138
Q

What is the active metabolite of Nitazoxanide?

A

Tizoxanide (desacetyl-nitazoxanide)

It is responsible for the antimicrobial effects of Nitazoxanide.

139
Q

Which parasites does Nitazoxanide inhibit the growth of?

A
  • C. parvum (sporozoites and oocytes)
  • G. intestinalis (trophozoites)
  • E. histolytica (trophozoites)
  • T. vaginalis (trophozoites)
  • Intestinal helminthes

It has a broad spectrum of activity against various parasitic infections.

140
Q

What happens to Nitazoxanide after oral administration?

A

It is rapidly hydrolyzed to tizoxanide, which undergoes conjugation to tizoxanide glucuronide

Maximum plasma concentrations occur 1-4 hours after administration.

141
Q

How is Tizoxanide primarily excreted?

A
  • Urine
  • Bile
  • Feces

Tizoxanide is more than 99.9% bound to plasma proteins.

142
Q

What is the mechanism of action of Nitazoxanide?

A

Interferes with the PFOR enzyme-dependent electron-transfer reaction

This reaction is essential to anaerobic metabolism in protozoan and bacterial species.

143
Q

What is the therapeutic efficacy of Nitazoxanide for G. intestinalis infection?

A

85%-90%

It is also effective for treating diarrhea caused by Cryptosporidia (56%-88%).

144
Q

What is the recommended dose of Nitazoxanide for children ages 12-47 months to treat cryptosporidiosis?

A

100 mg every 12 hours for 3 days

For children ages 4-11 years, the dose is 200 mg every 12 hours for 3 days.

145
Q

What are the side effects of Nitazoxanide?

A

Rare adverse effects, including a greenish tint to urine

Nitazoxanide is classified as a pregnancy category B agent.

146
Q

What is Paromomycin?

A

An aminoglycoside used to treat E. histolytica infection, cryptosporidiosis, and giardiasis

It is part of the neomycin/kanamycin family.

147
Q

What is the mechanism of action of Paromomycin?

A

Binds to the 30S ribosomal subunit

It shares this mechanism with neomycin and kanamycin.

148
Q

What is the drug of choice for treating intestinal colonization with E. histolytica?

A

Paromomycin

It is used in combination with metronidazole to treat amebic colitis.

149
Q

What are the common adverse effects associated with Paromomycin?

A
  • Abdominal pain
  • Cramping
  • Nausea
  • Vomiting
  • Steatorrhea
  • Diarrhea

Rarely, rash and headache may occur.

150
Q

What is the dosing recommendation for Paromomycin?

A

25-35 mg/kg/day in three divided oral doses

This applies to both adults and children.

151
Q

Fill in the blank: Paromomycin is used in pregnant women and for _______ resistant isolates.

A

metronidazole

It is an effective alternative when metronidazole is not suitable.

152
Q

What is pentamidine?

A

A positively charged aromatic diamine used as a broad-spectrum agent against several pathogenic protozoa and some fungi.

153
Q

What form is pentamidine marketed in?

A

As the di-isethionate salt for injection or as an aerosol.

154
Q

Which infection is pentamidine used to treat?

A

Early-stage T. brucei gambiense infection.

155
Q

Is pentamidine effective for late-stage T. brucei infections?

A

No, it is ineffective in the treatment of late-stage disease.

156
Q

What is an alternative agent for cutaneous leishmaniasis?

A

Pentamidine.

157
Q

What pneumonia does pentamidine prophylaxis target?

A

Pneumonia caused by Pneumocystis jiroveci (PJP).

158
Q

What is a less expensive alternative to pentamidine for early African trypanosomiasis?

A

Diminazene.

159
Q

What is known about the mechanism of action of diamidines like pentamidine?

A

The mechanism of action is unknown.

160
Q

Which transporter is responsible for pentamidine uptake?

A

TbAQP2 from the aquaglyceroporin gene family.

161
Q

What is the half-life of pentamidine after intravenous administration?

A

Several minutes to a few hours.

162
Q

What percentage of pentamidine is bound to plasma proteins?

163
Q

Is pentamidine well absorbed orally?

A

No, it is poorly absorbed orally.

164
Q

What is the treatment dosage for early-stage T. brucei gambiense using pentamidine?

A

4 mg/kg daily for 7 days.

165
Q

What are the typical doses for treating cutaneous leishmaniasis with pentamidine?

A

2-3 mg/kg IV or IM daily or every second day for 4-7 doses.

166
Q

What percentage of individuals show adverse effects from pentamidine?

167
Q

What are some adverse effects associated with intravenous pentamidine administration?

A

Hypotension, tachycardia, headache.

168
Q

What life-threatening condition may occur during pentamidine treatment?

A

Hypoglycemia.

169
Q

What renal side effect is associated with pentamidine?

A

Nephrotoxicity, with ~25% showing signs of renal dysfunction.

170
Q

What is sodium stibogluconate used for?

A

Treatment of leishmaniasis and other protozoal infections.

171
Q

What type of compound is sodium stibogluconate?

A

A pentavalent antimonial compound.

172
Q

How do pentavalent antimonials like sodium stibogluconate work?

A

They act as prodrugs that are reduced to the more toxic Sb3+ species.

173
Q

What is the standard dosage for sodium stibogluconate in treating cutaneous leishmaniasis?

A

20 mg/kg/d for 20 days.

174
Q

What are some common adverse effects of sodium stibogluconate?

A

Chemical pancreatitis, elevation of serum hepatic transaminases, bone marrow suppression.

175
Q

True or False: Most toxic reactions from sodium stibogluconate are irreversible.

176
Q

What is the elimination route for sodium stibogluconate?

A

In the urine.

177
Q

What is suramin primarily used for?

A

Treatment of African trypanosomiasis

Suramin has no clinical utility against American trypanosomiasis.

178
Q

When was suramin introduced into therapy?

A

1920

This followed research into the trypanocidal activity of certain dyes.

179
Q

What is the mechanism of action of suramin?

A

Unknown

A recent study suggested a role for lysosomal function and ISG75 family mediating suramin uptake.

180
Q

Why is suramin administered intravenously?

A

It is not absorbed after oral intake

This avoids local inflammation and necrosis associated with subcutaneous or intramuscular injections.

181
Q

What is the terminal elimination half-life (t1/2) of suramin?

A

41-78 days

182
Q

What percentage of suramin is bound to serum protein?

183
Q

What accounts for 80% of suramin’s elimination from the body?

A

Renal clearance

184
Q

What is the first-line therapy for early-stage T. brucei rhodesiense infection?

185
Q

What should be ensured before starting treatment for active African trypanosomiasis?

A

No CNS involvement

Treatment should not start until 24 hours after diagnostic lumbar puncture.

186
Q

What is the normal single dose of suramin for adults with T. brucei rhodesiense infection?

187
Q

What is the advised test dose of suramin for adults?

188
Q

What serious immediate reactions can occur with suramin?

A

Nausea, vomiting, shock, loss of consciousness

189
Q

What is a potential reaction in individuals with onchocerciasis when treated with suramin?

A

Mazzotti reaction

Symptoms include pruritic rash, fever, malaise, lymph node swelling, eosinophilia, arthralgias, tachycardia, hypotension, and possibly permanent blindness.

190
Q

What is the pediatric test dose of suramin?

191
Q

What should be done for patients who relapse after suramin therapy?

A

Treat with melarsoprol

192
Q

Suramin is known to inhibit many ______ and receptors.

A

trypanosomal enzymes

193
Q

True or False: Suramin is effective for late-stage African trypanosomiasis.

A

False

Very little suramin penetrates the CSF.

194
Q

What kind of activity does suramin exhibit against T. brucei gambiense?

A

High clinical activity

195
Q

What kind of pharmacokinetics does suramin display?

A

Complex pharmacokinetics with marked interindividual variability

196
Q

What type of solutions should be used for suramin?

A

Freshly prepared solutions

Solutions deteriorate quickly in air.

PHARMACOLOGY (sahrgeant) (3 decks)

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