Very common in several parts of the world.

They thrive in tropical climates, but they may also survive and reproduce in any area where people live in very crowded and unsanitary conditions.

Children› Very sensitive to the effects of most

antiprotozoal drugs, and more severe reactions can be expected when these drugs are used,› Many of these drugs do not have proven safety

and efficacy in children, and caution should be used.› In need to travel to an area of endemic

protozoal infections, the CDC should be consulted about the safest possible intervention.

Adults› Should be well advised about the need for

prophylaxis against various protozoal infections and the need for immediate treatment if the disease is contracted› Mark calendars as reminders of the days

before, during, and after exposure on which the drugs should be taken› Pregnant and nursing women should not use

these drugs.

› Pregnant women travelling to an area endemic with protozoal infections should be advised of the serious risk to the fetus.

Older adults› More susceptible to the adverse effect› Monitored closely› Patients w/ hepatic function are at

increased risk

A parasitic disease that has killed hundreds of people and even changed the course of history

Spread via the bite of an Anopheles mosquito, which harbors the protozoal parasites and carries it to humans

Plasmodium falciparum› Most dangerous type of protozoan› Infection acute, rapoidly fulmating disease

with high fever, severe hypotension, swelling and reddening of the limbs, loss of red blood cells and even death

Plasmodium vivax› Causes a milder form of the disease which

seldom results to death

Plasmodium malariae› Endemic in many tropical countries and

cause very mild signs and symptoms in the population› Can cause more acute disease in travelers

to endemic areas

Plasmodium Ovale› Rarely seen› In the process of being eradicated

Antimalarials› drugs are usually given in combination form to

attack the plasmodium at various stages of its life cycle.

  Quinine ( generic )› the first drug found to be effective in the

treatment of malaria, is now reserved for treatment of chloroquine-resistant infections combination with other agents. Quinine affects the DNA synthesis of the plasmodium, leading to an inability to reproduce effectively. The drug may lead to severe diarrhea and a condition called cinchonism ( nausea, vomiting, tinnitus and vertigo ) which makes it less desirable than newer, less toxic drugs. Quinine is toxic to the fetus and is classified as pregnancy category X.

 

Chloroquine ( Aralen ) › is currently the mainstay of antimalarial theraphy. This

drug enters the human red blood cells and changes the metabolic pathways necessary for the reproduction of the plasmodium. In addition, this agent is directly toxic to parasite to synthesize DNA, leading to a blockage of reproduction. It also have a serious adverse effects, such as hepatic toxicity, permanent eye damage, and blindness. Chloroquine is readily absorbed from the G.I tract with peak serum levels occurring in 1 to 6 hours. Use during pregnancy and lactation should be restricted to situations which the benefit clearly out weight the potential risk to the fetus.

 

Drugs in Focus

Hydroxychloroquine ( Plaquenil )› inhibits parasite reproduction, and by

blocking th synthesis of protein production, it can cause the death of the plasmodium. This drug is used in combination therapy, usually with primaquine, for greatest effectiveness. It is excreted slowly in the urine, primarily as unchanged drug. Use during pregnancy and lactation should be stricted to situations where the benefit clearly out weight the potential risk to the fetus or neonate.

 

Mefloquine ( Lariam )› increases the acidity of plasmodial food

vacuoles, causing cell rupture and death. In combination therapy, mefloquine is used in malarial prevention, as well as treatment. Mefloquine is a mixture of molecules that are absorbed, metabolized, and excreted at different rates. The terminal half life is 13 to 24 days. Metabolism occurs in the liver; caution should be used in patient with hepatic dysfunction. Pregnancy should be avoided during and for 2 months after completion of therapy. Mefloquine is teratogenic in preclinical studies. It also crosses into breast milk and can be very toxic to the baby. Breast feeding should be discontinued if this drug is essential for therapy.

Primaquine ( generic )› another very old drug for treating malaria,

similar to quinine, disrupts the mitochondria of the plasmodium. It is also causes death of gametocytes and exoerythocytic forms and prevents other forms from reproducing. Because of this action, it is especially useful in preventing relapses of P. vivax and P. malariae infections. It is absorbed and metabolized in the liver. Excretion occurs primarily in the urine.

 

Pyrimethamine ( Daraprim )› is used in combination with agents that act more

rapidly to suppress malaria by blocking the use of folic acid in protein synthesis by the plasmodium, eventually leading to inability to reproduce and cell death. Pyrimethamine is readily absorbed from the GI tract, with peak levels occurring within 2 to 6 hours. It is metabolized in the liver and has a half-life of 4 days. It usually maintains suppressive concentrations in the body for about two weeks. As with other antiprotozoals, pyrimethamine should not be used during pregnancy or lactation unless the benefit clearly outweightd the potential risk to the fetus or neonate.

THERAPEUTIC ACTIONS AND INDICATIONS

Research has demonstrated that the antimalarial agents are effective in interrupting plasmodial reproduction of protein synthesis in the red blood cell stage of the life cycle, as well as in the hepatic and gametocyte stages in some cases. Chemotherapeutic agents, which do not appear to affect the spo, are used for prophylaxis and treatment of acute attacts of malaria caused by susceptible starins of plasmodium.

Assessment: History and Examination› Screen for the following: history of allergy to

any of the antimalarials; liver dysfunction or alcoholism that might interfere with the metabolism and the excretion of the drug; porphyria or psoriasis, which could be exacerbated by the drug effects; retinal disease that could increase the visual disturbances associated with these could affect the fetus and could enter the breast milk and be toxic to the infant.

Physical assessment should be performed to established baseline data for assessment of the effectiveness of the drug and the occurrence of any adverse effects associated with the therapy. Assess CNS (reflexes and muscle strength). Perform retinal examination and auditory and ophthalmic screening to detect cautions for drug use and to evaluate changes that occur as a result of drug therapy. Perform liver evaluation and obtain liver function tests to determine appropriateness of thyerapy and to monitor for toxicity. Perform blood culture to determine which plasmodium species is causing the disease. Conduct examination of the skin (lesions, color, temperature, and texture) to monitor for adverse effects.

 

The patient receiving an antimalarial drug may have the following nursing diagnosis related to drug therapy:

Acute pain related to GI, CND and skin effects of drug

Disturbed sensory perception (kinesthetic, visual) related to CND effects

Deficient knowledge regarding drug therapy

 

Arrange for appropriate culture and sensitivity tests before beginning therapy to ensure proper drug for susceptible plasmodium species. Treatment may begin before tests result are known.

Administer the complete course of the drug to get the full beneficial effects. Mark a calendar for prophylactic doses. Uses combination therapy as indicated.

Monitor hepatic function and ophthalmologic examination before and periodically during treatment to effectively arrange to stop the drug if signs of failure or deteriorating vision occur.

Provide comfort and safety measures if CND effects occur (e.g., siderails and assistance with ambulation if dizziness and weakness are present) to prevent patient injury. Provide oral hygiene and ready access to bathroom facilities as needed to cope with GI effects.

Provide small, frequent, nutritious meals if GI upset is severe to ensure adequate nutrition. Monitor nutritional status and arrande a diety consultation as needed. Taking the drug with food may also decrease GI upset.

Ensure that the patient is instructed concerning the appropriate dosage regimen to enhance patient knowledge about drug thjerapy and to promote compliance.

Take safety precautions, including changing position slowly and avoiding driving and hazardous tasks, if CND effects occur.

Take the drug with meals and try small, frequent meals if GI upset is a problem.

Report blurring visions, which could indicate retinal damage; loss of hearing or ringing in the ears, which could indicate CNS toxicity; and fever or worseneng of condition, which could indicate a resistant strain or noneffective therapy.

Monitor patient response to the drug (resolution of malaria of prevention of malaria).

Monitor for adverse effects (orientation and affect, nutritional state, skin color and lesions, hepatic function, and visual and auditory changes).

Evaluate the effectiveness of the teaching plan (patient can name the drug, dosage, possible adverse effects to watch for, and specific measures to help avoid adverse effects).

Monitor the effectiveness of comfort and safety measure and compliance with the regimen.

Protozoan is a parasitic cellular organism. Its life cycle includes a parasitic phase inseide human tissue or cell.

Malaria is the most coomon protozoal infection. It is spread to human by the bite of an Anopheles mosquito.

The signs and symptoms of amlaria are related to the destruction of red blood cells and toxicity to the liver.

Treatment for malaria aims at attacking the parasite at the various stages of its development inside and outside the human body.

 

Amoebiasis› -an intestinal infection caused by

Entamoeba histolytica, is often known as amebic dysentery. E. histolytica has 2 stages, 1) cystic, in w/c protozoan can live for lng periods outside the body or in the human intestine and 2) trophozoite stage in the ideal environment – the human large intestine. Early signs of amoebiasis include mild to fulminate diarrhea. Some individuals can become carriers of the disease w/o having any signs or symptoms.

Leishmaniasis› -a disease caused by a protozoan that is

passed from sand flies to humans. The sand fly injects an asexual form of this flagellated protozoan, called promastigote, in the human body where it is rapidly attacked and digested by human macrophages. These amastigotes can cause serious lesions in the skin, the viscera, or the mucous membranes of the host.

 

Trypanosomiasis -is caused by infection with

trypanosome. African sleeping sickness, w/c is caused trypanosome brucei gambiense, is transmitted by tsetse fly.

Chagas disease w/c is caused by trypanosome cruzi, is almost endemic in south African countries.

 

Trichomoniasis -w/c is caused by another flagellated

protozoan, trichomonas vaginalis, is a common cause of vaginitis. This infection is usually spread during sexual intercourse by men who have no signs and symptoms of infection. This causes reddened, inflamed vaginal mucosa, itching, burning and yellowish-green discharge.

 

Giardiasis› -w/c is caused giardia lamblia, is the most

commonly diagnosed intestinal parasite in the US. This forms cysts, w/c survive outside the body and allow transmission through contaminated water or food and tropozoites, w/c break out of the cysts in the upper small intestine and eventually cause signs and symptoms of disease. Diarrhea, rotten-egg smelling stool, and pale mucous filled stool are commonly seen. Some patient may experience epigastric distress, wt loss, and malnourishment as a result of the invasion of the mucosa.

Pneumocystis carinii Pneumonia -is an endemic protozoan that does not

usually cause illness in humans. This disease is the most common opportunistic infection in patiens with AIDS.

 

Metronidazole (flagyl, metrogel, noritate), w/c is used to treat amoebiasis, trichomoniasis, and giardiasis, is well absorbed orally, reaching peak 1-2hrs. with a half-life of 8-15hrs. excretion in the urine.

  Nitazoxanide (alinia), is used to treat diarrhea caused

by crytosporidum paruum (>1y/o) or giardia lamblia (1-11y/o). it is rapidly absorbed after oral administration, reaching peak levels 1-4hrs. it is metabolized in the liver and excreted in the urine and feces, has a half-life of 8-12hrs. it is not known if nitazonide crosses the placenta or enters breast milk.

Atovaquone (mepron) , w/c is especially active against PCP, is

slowly absorb and highly protein boundin circulation. It is excreted slowly through the feces, with half-life 67-76hrs. use during pregnancy and lactation should be limited to those situations in w/c the potential risks to the fetus or neonate.

Pentamidine (nebupent, pentam300) is used as an inhalation agent and a systemic agent in the treatment of PCP and as a systemic drug in the treatment of panosomiasis and leishmaniasis. It is readily absorbed through lungs. Excretion in the urine. The safety and efficacy of this during pregnancy and lactation, and for children, have not been established.

  Tinidazole(tindamax) treatment for trichomoniasis,

giardiasis and amebiasis. Rapidly absorbed after oral administration, reaching peak levels within 60-90mins. It is excreted in the urine with a half-life to 12-14hrs. it crosses the placenta and enters breast milk. It should never be combined with alcohol and should be cautiously with liver or renal dysfunction.

 

Therapeutic Actions and Indications Antiprotozoal agents act to inhibit DNA synthesis in

susceptible protozoa, leading to the inability to reproduce and subsequent cell death.

These drugs are indicated for the treatment of infections caused by susceptible protozoa.

Contraindications and Cautions Contraindications include the presence of any known allergy

or hypersensitivity to any of these drugs and pregnancy because drug effects on developing fetal DNA and proteins can cause fetal abnormalities and even death.

Caution should be taken in the presence of CNS disease because of possible exacerbation when the drug affects the CNS; Hepatic disease because of possible exacerbation when hepatic drug occur; candidiasis because of the risk of super infections; and lactation, because these drugs may pass into breast milk and could have severe adverse effects on the infant.

Adverse Effects Adverse effects that can be seen with

these antiprotozoal agents include such CNS effects as headache, dizziness, ataxia, loss of coordination, and peripheral neuropathy related to drug effects on the neurons.

GI effects include nausea, vomiting, diarrhea, unpleasant taste, cramps, and changes in liver function. Super infections also can occur when the normal flora is disrupted.

ASSESSMENT: History, Examination, and Physical Assessment

History of allergy Liver dysfunctions Pregnancy Lactation CNS disease Candidiasis

Physical Assessment Conduct examination of the CNS to

check reflexes and of muscle strength to detect cautions for drug use and to evaluate changes that occur as a result of drug therapy.

Evaluate liver and liver function. Examine the skin and mucous

membranes.  

-The patient receiving an antiprotozoal drug may have the following nursing diagnoses related to drug therapy.

Acute pain related to GI and CNS effects of drug Imbalanced Nutrition: Less than Body Requirements

related to severe GI effects of drug Disturbed Sensory Perception (Kinesthetic, Visual)

related to CNS effects Deficient knowledge regarding drug therapy

Arrange for appropriate culture and sensitivity tests before beginning therapy to ensure proper drug for susceptible organisms. Treatment may begin before test results are known.

Administer the complete course of the drug to get the full beneficial effects. Use combination therapy as indicated.

Monitor hepatic function before and periodically during treatment to arrange to effectively stop the drug if signs of failure or worsening liver function occur.

Provide comfort and safety measure if CNS effects occur, such as side rails and assistance with ambulation if dizziness and weakness are present, to prevent injury to the patient. Provide oral hygiene and ready access to bathroom facilities as needed to cope with GI effects.

Arrange for treatment of super infections as appropriate to prevent severe infections.

Provide small, frequent, nutritious meals if GI upset is severe to ensure proper nutrition. Monitor nutritional status and arrange a dietary consultation as needed. Taking the drug with food may also decrease GI upset

Ensure that the patient is instructed about the appropriate dosage regimen to enhance patient knowledge about drug therapy and to promote compliance.

The patient should: Take safety precautions including changing position slowly

and avoiding driving and hazardous task if CNS effects occur Take the drug with meals and take small frequent meals if GI

upset is a problem Report severe GI problems with interference with nutrition;

fever and chills, which may indicate the presence of a super infection; and dizziness, and usual fatigue or weakness which may indicate CNS effects

Monitor patient response to the drug (resolution of infection and negative cultures for parasite)

Monitor for adverse effects (Orientation and affect, Nutritional State, Skin color and Lesion, Hepatic Function, and occurrence of super infections

Evaluate effectiveness of teaching plan (patient can name the drug, dosage, possible adverse effects to watch for and specific measures to help avoid adverse effects)

Monitor the effectiveness of comfort and safety measures and compliance with th

A protozoan is a parasitic cellular organism. Its life cycle includes parasitic phase inside human tissues or cells.

Malaria, which occurs in many tropical parts of the world, has been spreading in recent years because of resistance to insecticides occurring in the Anopheles mosquito.

Malaria is caused by Plasmodium protozoa, which must go through a cycle in the Anopheles mosquito before being passed to humans by the mosquito bite. Once inside a human, the protozoa invade red blood cells.

   

Intestine-invading Worms› Live only in intestinal tract

Proper Diagnosis› Stool examination for ova(eggs) and parasites

Treatment› Antihelminthic drug

Preventive Measures› Thorough hand washing after use of the toilet› Frequent laundering of bed linens and underwear in

very hot, chlorine- treated water› Disinfection of toilet and bathroom areas after each

use› good personal hygiene to wash away ova

Nematodes› or roundworms› commonly encountered pinworms, whipworms,

threadworms, ascaris and hookworms› causes diseases that range from mild to

potentially deadly Pinworms› stays in the intestine cause little discomfort

except for perianal itching or occasionally vaginal itching› infection with pinworms is the most common

helminthic infection among school-age children

Whipworms› attach themselves to the wall of the colon› causes colic and bloody diarrhea› in severe cases, whipworm infestation may result in

prolapse of the intestinal wall & anemia related to blood loss

Threadworms› more pervasive than most of the other helminths› after burrowing into the wall of the small intestine,

female worms lay eggs, w/c hatch into larvae that invade many body tissues, including the lungs, liver and heart.

› Death may occur from pneumonia or from lung or liver abscesses that result from larval invasion

Ascaris› Ascaris infection is the most prevalent helminthic

infection › Occur whenever the sanitation is poor› Initially the individual ingests fertilized roundworm

eggs, w/c hatch in the small intestine & make their way to the lungs, where they may cause cough, fever & other signs of a pulmonary infiltrate› Can cause abdominal distention and pain› In the most severe cases, intestinal obstruction

by masses of worms can occur

Hookworms› Attach themselves to the small intestine of

infected individuals & suck blood from the walls of the intestine› Damages the intestinal wall and can cause

severe anemia with lethargy, weakness and fatigue› Mal absorption problems may occur as the small

intestinal mucosa is altered› Treatment for anemia & fluid &electrolyte

disturbances is an important part of the therapy for this infection

Platyheliminthes: cestodes› Platyhelminthes (flatworms) include the cestodes

(tapeworms) that live in the human intestine & the flukes (schistosomes) that invade other tissues as part of their lifecycles

› Cestodes are flat segmented flatworms with a head, scolex, and a variable number of segments that grow from the head

› Persons with a tapeworm may experience some abdominal discomfort and distention as well as weight loss because the worm eats the ingested nutrients

› Many infected patients require a great deal of psychological support when they excrete parts of the tapeworm or when the worm comes out the mouth or nose, which may occur occasionally

Tissue- invading worm infections› Some of the worms that invade the body exist

outside the intestinal tract & can seriously damage the tissues they invade

› They can be more difficult to treat Trichinosis› Disease caused by the ingestion of the encysted

larvae of the roundworm Trichinella spiralis, in undercooked pork

› The larvae of this worm, which are deposited in the intestinal mucosa, pass into the bloodstream & are carried throughout the body

› Can cause an inflammatory reaction in cardiac muscle and in the brain

› Fatal pneumonia, heart failure, and encephalitis may occur

› Best treatment for trichinosis is prevention › The larvae ingested by humans in undercooked pork,

freezing pork meat, monitoring the food eaten by pigs, and instructing people in the proper cooking of pork can e most beneficial

  Filariasis› Refers to the infection of the blood and tissues of healthy

individuals by worm embryos, which are injected by biting insects

› These thread like embryos, or filariae, can overwhelm the lymphatic system & cause massive inflammatory reactions.

› May lead to severe swelling of the hands, feet, legs, arms, scrotum, or breast – a condition called elephantiasis

Schistosomiasis› Infection caused by snails › Common problem in parts of Africa, Asia, and

certain South American & Caribbean countries› People become Infected when they become

contact with the infested water › The larvae attached to the skin & quickly burrow

into the bloodstream & lymphatics› After they move into the lungs, and later the

liver, they mature into adult worms that mate & migrate to the intestines and urinary bladder

Signs and symptoms › may include a pruritic rash where the larva

attaches to the skin, which is often called swimmer’s itch› affected individuals may experience several

weeks of fever, chills, headache› chronic or severe infestation may lead to

abdominal pain and diarrhea, as well as blockage of blood flow to areas of the liver, lungs and CNS

Antihelmintics› antihelmintic drugs act on metabolic pathways

that are present in the invading worm but absent or significantly different in the human host› Mebandazole is the most commonly used of all

the antihelmintics, is effective against pinworms, roundworms, whipworms, and hookworms› Very little of the mebendazole is absorbed

systematically, it has a few adverse effects , the drug is not metabolized in the body, it is excreted unchanged in the feces

Indicated for the treatment of infections of worms

Anthelminthics interfere metabolic processes in particular worm

 

Known allergy to any anthelminthics drug

During lactation and pregnancy Presence of renal and hepatic disease  

Abdominal discomfort Diarrhea Pain Headache and dizziness Fever Chills Malaise Prutitus Loss hair Renal failure Severe bone marrow depression    

Drug Name Classification Mode of action pharmacokinetics PharmacotherapeuticsAbsorption Distribution Metabolism Excretion

Mebendazole(vermox)

Anthelmintic drugs

Disintegrates microtubule of helminthes. thus, blocks glucose uptake and helminthes will not maintain energy level and subsequently will destroy them

Oral Enters the blood and distributed through systemic circulation

Blood carrying mebendazole will go to the liver to metabolize

urine Shouldn’t be used during pregnancy and lactationIt should be used only after the causative worm has been identified

Albendazole(albenza)

Anthelmintic drugs

Disintegrates microtubule of helminthes. thus, blocks glucose uptake and helminthes will not maintain energy level and subsequently will destroy them

poorly absorbed in the GI tract

Peak level serum at 4-5 hours

liver urine Shouldn’t be used during pregnancy and lactationIt should be used only after the causative worm has been identified

Albendazole(albenza)

Anthelmintic drugs

Disintegrates microtubule of helminthes. thus, blocks glucose uptake and helminthes will not maintain energy level and subsequently will destroy them

poorly absorbed in the GI tract

Peak level serum at 4-5 hours

liver urine Shouldn’t be used during pregnancy and lactationIt should be used only after the causative worm has been identified

Ivermectin(stromectol)

Anthelmintic drugs

Block chloride channels in muscle & nerves of helminthes.this actions are effects on gamma aminobutyric acid(GABA) receptors in helminthes interfere with function of nervous system in thread worms and other parasite. The paralyzed worm may die

Single oral dose

Peak plasma level of 1-3 hours

Concentrates in the liver and fatty tissues Half life of 16 hours

Shouldn’t be used during pregnancy and lactation

Piperazine(multifuge)

Anthelmintic drugs

Blocks the action of acetylcholine on the muscle of parasite, then the parasite will be paralyzed and eliminated from bowel of normal peristalsis

Oral Peak plasma level of 1-3 hours

Metabolized in the liver

urine Shouldn’t be used during pregnancy and lactation

Praziquantel(biltricide)

Anthelmintic drugs

Interferes muscle function of flukes and helminthes and cause local destruction of the integument of organism

Oral Peak plasma level of 1-3 hours

Metabolized in the liver and a half life of 0.8-1.5 hours

urine Shouldn’t be used during pregnancy and lactation

Pyrantel(antiminth, pin-rid, pin-x, reese’s pinworm,combantriln)

Anthelmintic drugs

Pyrantel is adepolarizing neuromuscular blocker similar with succinycholine. Causes paralysis and contraction of the muscle in worms .the parasite is eliminated from the body by normal peristalsis

Not absorbed in the GI tract

Peak plasma level of 1-3 hours

Metabolized in the liver

Feces Shouldn’t be used during pregnancy and lactation

Thiabendazole(mintezol

Anthelmintic drugs

Attacks the metabolic processes essential in helminthes

GI tract Peak plasma level of 1-2 hours

Metabolized in the liver

Shouldn’t be used during pregnancy and lactation

Assessment› History and examination› History of allergies to a drug› Renal or liver dysfunction› Drug history: use of Albendazole› CNS: orientation, affection› Skin: color, lesions, texture› GI: abdominal and liver evaluation hepatic function test› GU: renal function test

  Nursing Diagnosis› Fear related to communication problems› Deficient knowledge related to drug therapy

 

Implementation› Provide comfort and safety measures, small frequent

meals, safety precautions, hygiene measures, maintenance of nutrition

› Monitor nutritional status› Provide patient teachings regarding drug name, dosage

regimen, adverse effects precautions to report, and hygiene measures to observe

Evaluation› Evaluate the drug effects› Monitor for adverse effects› Monitor for drug-drug interactions› Evaluate effectiveness of patient teaching program› Evaluate effectiveness of comfort and safety measures

 

Patient Teachings Teach the drug that will be given to that type

of disease Teach the importance of the drug Teach the route and dosage regimen of the

drug Teach the phramacotherapeutics of the drugs Teach the effects of the drugs Teach the adverse and the side effects of the

drug