POTASSIUM CITRATE Indication Doses Contra Indications and Adverse Effects

Indications:

Urinary alkalinizer, when Na Citrate is contraindicated, prevention of uric acid nephrolithiasis and calcium renal stones.

Doses & Administrations:
Administration *dilute adequately with water to minimize gastrointestinal injury * take after meals to avoid saline laxative effect * palatability of oral solution enhanced by chilling ADULT DOSE: FOR URIC ACID STONE: 30 to 60 milliequivalents/day orally in three or four doses with meals or within 30 minutes after meals. ............Mix in 10-30 ml of water or juice................... Maximum daily dosage is 100 milliequivalents PEDIATRIC DOSE: 5-10 mEq after meals and at bed time. NOTE: 1 gm Potassium Citrate = 3.08 mMoles (9.25mEq) Citrate 9.03 mMoles (9.03mEq) potassium

Contra Indications:
Addison's disease, untreated adynamia episodica hereditaria anuria, dehydration, acute heat cramps, hyperkalemia myocardial damage, severe renal impairment with oliguria or azotemia

Precautions:
Monitor serum electrolytes, especially bicarbonate, in patients with renal disease Potassium citrate in patients with decreased urinary output, especially in the presence of hypocalcemia

Pregnancy Status:
CATEGORY "C"

Renal Failure Doses:
CONTRAINDICATED in severe renal impairment, oligouria and azotemia.
Lactation Status:
SAFE

Interactions:
k-SPARING DIURETICS It may cause an increase in toxicity of following drugs: quinine, quinidine, amphetamines, ephedrine. It decreases effectiveness of: lithium, MTX, and tetracyclines.

Adverse Effects:
SERIOUS: alkalosis electrocardiographic abnormalities (associated with hyperkalemia) hyperkalemia

Nursing Considerations:
Use well diluted, chilled solution.Use the solution with in 1 hour of preparation. Watch patient for signs of hyperkalemia, and check bicarbonate levels periodically. Do not administer on an empty stomach.

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Unknown Contraindications, dose, indication, POTASSIUM CITRATE

DINOPROSTONE Doses Contra Indications Interactions and Adverse Effects

Indications:

Induction of labor especially in patients with favorable induction feature or maternal contraindications.

Doses & Administrations:
Parenteral: Abortion (intraamniotic) 40 mg transabdominally into the intact amniotic to induce mid trimester abortion (after 15 weeks). Abortion (Extraamniotic): By I/V infusion: 1 mg/hr or 5 mg bolus every 2 to 3 hrs to a total dose of 15 mg. Labor Induction (I/V): By I/V infusion: 5 mcg/minute. Intravaginal: 3mg to be inserted high into the posterior fornix, a second tablet may be inserted after six to eight hours if labor is not established. (Maximum dose 6mg).

Contra Indications:
Hypersensitivity to prostaglandin, acute pelvic inflammatory disease or active cardiac, pulmonary, renal or hepatic disease, patients with history of caesarean section or major uterine surgery.

Precautions:
Glaucoma or raised intraocular pressure, asthma or history of asthma, infected endocervical lesions, acute vaginitis, epilepsy, diabetes mellitus, anemia, jaundice.

Pregnancy Status:
Category "C".

Renal Failure Doses:
Dose adjustment is not required.

Lactation Status:
Unknown.

Interactions:
Prostaglandin inhibiter (aspirin, indomethacin, NSAIDS) oxytocin and ethanol.

Adverse Effects:
Nausea, vomiting, headache, chills, shivering, backache, weakness and muscle cramps.

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Unknown Adverse Effects, Contraindications, DINOPROSTONE, Intrerations

Dexamethasone Indications Doses Contra Indications and Interactions

Indications:Primary or secondary adrenocortical insufficiency; allergy and anaphylaxis, shock, crohn's disease, ulcerative colitis, rheumatic arthritis, skin disorders and cerebral edema.

Doses & Administrations:
Oral: Adult: 0.5-9mg daily individed doses depending on the disease and response of the patient. Maximum: 15 mg daily. Pediatric: 0.03 - 0.15 mg/kg/day every 6 to 12 hours or 1.5mg/m2 every 6 to 12 hours. Parenteral (I/M or I/V): Adult : 0.5 - 9mg daily in divided dose depending an disease being treated. day by constant I/V infusion after bolus dose of 20 mg. by constant I/V infusion after bolus dose of 20mg. I/M every 6 hours as required for 2-10 days. Pediatric: Neonates : 0.2 - 0.5 mg/kg followed by 0.1 mg/kg po or I/V every 6 to 8 hours. Cerebral edema: 1.5 mg/kg/day every 4 to 6 hours for 5 days. Maximum : 6 mg/kg/day.

Contra Indications: Hypersensitivity to Dexamethasone or other component of the preparation dendritic keratitis, varicella and tuberculosis of the eye.

Precautions:Use cautiously in patients with renal insufficiency, diabetes mellitus, hypertension, osteoporosis, glaucoma, active or latent peptic ulcer, viral infection, tuberculosis; avoid abrupt withdrawal, monitor growth in infants and children who are on iron therapy.

Pregnancy Status:Category "C".

Renal Failure Doses:No dosage adjustment is required.

Lactation Status:Unsafe.

Interactions:Phenytoin, ephedrine, rifampicin, barbiturate may decreased blood level of cortico steroids, avoid use of live virus vaccine. Decrease absorption of calcium and phosphorus, urinary excretion of ascorbic acid, calcium, potassium, zinc, nitrogen. Increase blood glucose, triglycerides, cholesterol. Increase need for B6, Ascorbic acid, folate and vitamin D.

Adverse Effects:
Glucoma cataract formation secondary ocular infection and thinning of the cornea.

Nursing Considerations:
- Monitor baseline body weight, temperature, pulse and respiratory rate. - Monitor fluid balance. - Taper systemic steroid carefully. prolonged sore throat and unusual weight gain. - Monitor Baseline body weight, temperature, Pulse and Respiratory. - Monitor fluid balance. - Taper systemic steroids carefully. - Teach patient to report if stool black/Tarry, Muscle weakness, Prolonged sore throat and unusal weight gain. ---------------------------------------------------------------- IV DILUTION: 0 to 50 mg/ 50 ml...OVER 30 MIN. 51 to 100 mg/ 100 ml IN D5W / NS CAN BE GIVEN BY IV PUSH: Over 1 minute to several min. if dose is < 10 mg.

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Unknown Contraindications, Dexamethasone, doses, Intrerations

Bronchodilators and Antiasthma Drugs Contraindicationa Precautions and Intreractions

Bronchodilators and Antiasthma Drugs:
Within the past few years a number of new drugs have been introduced to treat respiratory disorders, such as
bronchial asthma and disorders that produce chronic airway obstruction.  bronchodilators, drugs that have been around for a long time but are still effective in specific instances, and the newer antiasthma drugs that have proven to be highly effective in the prophylaxis (prevention) of breathing difficulty.
Asthma is a reversible obstructive disease of the lower airway. With asthma there is increasing airway
obstruction caused by bronchospasm and bronchoconstriction, inflammation and edema of the lining of the bronchioles,and the production of thick mucus that can plug the airway .

There are three types of asthma:
1. Extrinsic (also referred to as allergic asthma and caused in response to an allergen such as pollen, dust, and animal dander)
2. Intrinsic asthma (also called nonallergic asthma and caused by chronic or recurrent respiratory infections, emotional upset, and exercise)
3. Mixed asthma (caused by both intrinsic and extrinsic factors)

Extrinsic or allergic asthma causes the IgE inflammatory response. With exposure, the IgE antibodies
are produced and attach to mast cells in the lung. Reexposure to the antigen causes them to bind to the IgE
antibody, releasing histamine and other mast cell products. The release of these products causes bronchospasm, mucous membrane swelling, and excessive mucous production. Gas exchange is impaired,
causing carbon dioxide to be trapped in the alveoli so that oxygen is unable to enter.identifies the
asthmatic pathway from both intrinsic and extrinsic stimulus.
Other disorders of the lower respiratory tract include emphysema (lung disorder in which the terminal bronchioles or alveoli become enlarged and plugged with mucus) and chronic bronchitis (chronic
inflammation and possibly infection of the bronchi).
Chronic obstructive pulmonary disease (COPD) is the name given collectively to emphysema and chronic
bronchitis because the obstruction to the airflow is present most of the time. Asthma that is persistent and
present for most of the time may also be referred to as COPD.

BRONCHODILATORS

A  bronchodilator is a drug used to relieve bronchospasm associated with respiratory disorders, such as
bronchial asthma, chronic bronchitis, and emphysema.These conditions are progressive disorders characterized by a decrease in the inspiratory and expiratory capacity of the lung. Collectively, they are often referred to as COPD.
The patient with COPD experiences dyspnea (difficulty breathing) with physical exertion, has difficulty inhaling
and exhaling, and may exhibit a chronic cough.The two major types of bronchodilators are the sympathomimetics and the xanthine derivatives. The anti-cholinergic drug ipratropium bromide (Atrovent) is
used for bronchospasm associated with COPD, chronic bronchitis, and emphysema.

Bronchodilators: Sympathomimetic
Examples of sympathomimetic bronchodilators include albuterol (Ventolin), epinephrine (Adrenalin), salmeterol (Serevent), and terbutaline (Brethine). Many of the sympathomimetics used as bronchodilators have the subclassification of beta-2 (2) receptor agonists (eg,albuterol, salmeterol, and terbutaline). Additional information concerning the various sympathomimetic

ACTIONS
When bronchospasm occurs, there is a decrease in the lumen (or inside diameter) of the bronchi, which
decreases the amount of air taken into the lungs with each breath. A decrease in the amount of air taken into
the lungs results in respiratory distress. Use of a bronchodilating drug opens the bronchi and allows more air
to enter the lungs, which in turn, completely or partially relieves respiratory distress.

USES
Sympathomimetics  (drugs that mimic the sympathetic nervous system) are used primarily to treat reversible airway obstruction caused by bronchospasm associated with acute and chronic bronchial asthma,exercise induced bronchospasm, bronchitis, emphysema, bronchiectasis (abnormal condition of the bronchial tree), or other obstructive pulmonary diseases.

ADVERSE REACTIONS
Administration of a sympathomimetic bronchodilator may result in restlessness, anxiety, increase in blood
pressure, palpitations, cardiac arrhythmias, and insomnia. When these drugs are used by inhalation, excessive
use (eg, over the recommended times) may result in paradoxical bronchospasm.

CONTRAINDICATIONS, PRECAUTIONS,
AND INTERACTIONS
The sympathomimetic bronchodilators are contraindicated in patients with known hypersensitivity to the
drug, cardiac arrhythmias associated with tachycardia, organic brain damage, cerebral arteriosclerosis, and narrow angle glaucoma. Salmeterol is contraindicated during acute bronchospasm. The sympathomimetics are used cautiously in patients with hypertension, cardiac dysfunction, hyperthyroidism, glaucoma, diabetes, prostatic hypertrophy, or a history of seizures. The sympathomimetic drugs are used cautiously during pregnancy (all are Pregnancy Category C, except terbutaline, which is Pregnancy Category B), and lactation.
When the sympathomimetics are used concurrently with other sympathomimetic drugs , additive adrenergic effects can occur. When used with the monoamine oxidase inhibitors, the patient is at increased risk for a hypertensive crisis.
When the sympathomimetics are administered with a adrenergic blocker, the drugs may inhibit the cardiac,
bronchodilating, and vasodilating effects of the sympathomimetic. When a  blocker such as propranolol is
administered with a sympathomimetic such as epinephrine, an initial hypertensive episode may occur followed
by bradycardia. Concurrent use of the sympathomimetics with oxytocic drugs may result in severe hypotension. When the sympathomimetics are administered with theophylline there is an increased risk for cardiotoxicity. When epinephrine is administered with insulin or oral hypoglycemic drugs, the patient may require an increased dose of the hypoglycemic drug.

Bronchodilators: Xanthine Derivatives
Examples of the  xanthine derivatives (drugs that stimulate the central nervous system [CNS] resulting in
bronchodilation, also called methylxanthines) are theophylline and aminophylline. 

ACTIONS 
The xanthine derivatives, although a different class of drugs, also have bronchodilating activity by means of their direct relaxation of the smooth muscles of the bronchi.

USES
The xanthine derivatives are used for symptomatic relief or prevention of bronchial asthma and reversible
bronchospasm associated with chronic bronchitis and emphysema.


ADVERSE REACTIONS
Adverse reactions associated with administration of the xanthine derivatives include nausea, vomiting, restlessness, nervousness, tachycardia, tremors, headache, palpitations, increased respirations, fever, hyperglycemia,and electrocardiographic changes.


CONTRAINDICATIONS, PRECAUTIONS,
AND INTERACTIONS

The xanthine derivatives are contraindicated in those with known hypersensitivity, peptic ulcers, seizure disorders (unless well controlled with appropriate anticonvulsant medication), serious uncontrolled rrhythmias,
and hyperthyroidism.
The xanthine derivatives are used cautiously in patients older than 60 years, those with cardiac disease,
hypoxemia, hypertension, congestive heart failure, or liver disease. Aminophylline, dyphylline, oxtriphylline,
and theophylline are Pregnancy Category C drugs and are used cautiously during pregnancy and lactation.
When xanthine bronchodilators are administered with sympathomimetic drugs, additive
CNS and cardiovascular effects may occur. If a patient eats large amounts of charcoal-broiled foods while taking the xanthines, a decrease in the therapeutic effect of the xanthines may occur. Certain foods contain xan
thine (eg, coffee, colas, or chocolate) and may increase the risk of cardiac and CNS adverse reactions.Cigarettes, nicotine gum and patches, barbiturates,phenytoin, loop diuretics, isoniazid, and rifampin may decrease the effectiveness of the xanthines. There is an increased risk of xanthine toxicity when the drugs are administered with influenza vaccination, oral contraceptives, glucocorticoids, -adrenergic blockers, cimetidine, macrolides, thyroid hormones, or allopurinol.

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Unknown Bronchodilators and Antiasthma Drugs, Contraindications, Interactions, Precautions

Narcotic Analgesics ACTIONS USES ADVERSE REACTIONS and CONTRAINDICATIONS

Pain is a complex occurrence that is uniquely experienced by each individual. It has been defined as the emotional and sensory perceptions associated with real or Acute pain is a warning that something is not right in the body. Chronic pain is pain that persists beyond the expected time for healing. Analgesics are drugs that relieve pain. The narcotic analgesics are con-trolled substances used to treat moderate to severe pain. Nurses must be knowledgeable concerning pain assessment and management if the patient’s pain is to be adequately managed. Despite advances in technology and pharmacologic measures, evidence exists indicating that for many, pain is not managed adequately.Drugs that counteract the effects of the narcotic analgesics are the narcotic antagonists. These drugs compete with the narcotics at the receptor sites and are used to reverse the depressant effects of the narcotic analgesics.

NARCOTIC ANALGESICS

Opioid analgesics are the narcotic analgesics obtained from the opium plant. More than 20 different alkaloids are obtained from the unripe seed of the opium poppy plant. The analgesic properties of opium have been known for hundreds of years. The narcotics obtained from raw opium (also called the opiates, opioids, or opiate narcotics) include morphine, codeine, hydrochlorides of opium alkaloids, and camphorated tincture of opium. Morphine, when extracted from raw opium and treated chemically, yields the semisynthetic narcotics hydromorphone, oxymorphone, oxycodone, and heroin.Heroin is an illegal narcotic in the United States and is not used in medicine. Synthetic narcotics are those man-made analgesics with properties and actions simi-lar to the natural opioids. Examples of synthetic narcotic analgesics are methadone, levorphanol, remifen-tanil, and meperidine. Additional narcotics are listed in the Summary Drug Table: Narcotic Analgesics.

ACTIONS

Narcotic analgesics are classified as agonists, partial agonists, and mixed agonists-antagonists. The agonist binds to a receptor and causes a response. A partial agonist binds to a receptor, but the response is limited (ie, is not as great as with the agonist). Antagonists bind to a recep-tor and cause no response. An antagonist can reverse the effects of the agonist. This reversal is possible because the antagonist competes with the agonist for a receptor site.

Drugs that act as antagonists are discussed at the end of this chapter. An agonist-antagonist has properties of
both the agonist and antagonist. These drugs have some agonist activity at the receptor sites and some antagonist activity at the receptor sites.
Classification of the narcotic analgesics is based on their activity at the opioid receptor sites. Although five
categories of opioid receptors have been identified, only three of these receptors affect the action of the narcotic analgesics:
• mu
• kappa
• delta
The narcotic agonists have activity at the mu and kappa receptors (and possi-bly the delta sites). Remifentanil is a very short-acting agonist with potent analgesic activity. It is a mu opioid agonist with rapid onset, peak effect, and short duration of action. The mixed agonist-antagonist drugs act on the mu receptors by competing with other substances at the mu receptor (antagonist activity) and are agonists at other receptors. Partial agonists have limited agonist activity at the mu receptor. The actions of the narcotic analgesics on the various organs and structures of the body (also called secondary pharmacological effects) are

USES

The major use of the narcotic analgesic is to relieve or manage moderate to severe acute and chronic pain. The ability of a narcotic analgesic to relieve pain depends on several factors, such as the drug, the dose, the route of administration, the type of pain, the patient, and the length of time the drug has been administered. Morphine is the most widely used opioid and an effective drug for moderately severe to severe pain. Morphine is considered the prototype or “model” narcotic. Morphine’s actions, uses, and ability to relieve pain are the standards to which other narcotic analgesics are often compared.Other narcotics, such as meperidine and levorphanol, are effective for the treatment of moderate to severe pain. For mild to moderate pain, the primary health care provider may order a narcotic such as codeine or pentazocine.
In addition to the relief or management of moderate to severe acute and chronic pain, the narcotic analgesics may be used for the following reasons:
• To lessen anxiety and sedate the patient before surgery. Patients who are relaxed and sedated when
anesthesia is given are easier to anesthetize (requiring a smaller dose of an induction anesthetic), as
well as easier to maintain under anesthesia
• Support of anesthesia (ie, as an adjunct during
anesthesia)
• Obstetrical analgesia
• Relief of anxiety in patients with dyspnea associated
with pulmonary edema
• Intrathecally or epidurally for pain relief for
extended periods without apparent loss of motor,
sensory, or sympathetic function
• Relief of pain associated with a myocardial infarc-
tion (morphine)
• Management of opiate dependence (levomethadyl)
• Detoxification of and temporary maintenance of
narcotic addiction (methadone)
• To induce conscious sedation before a diagnostic
or therapeutic procedure in the hospital setting
• Treatment of severe diarrhea and intestinal
cramping (camphorated tincture of opium)
• Relief of severe, persistent cough (codeine, although
the drug’s use has declined)

Use in Management of Opioid Dependence

Two opioids are used in the treatment and management of opiate dependence: levomethadyl and methadone.Levomethadyl is given in an opiate dependency clinic to maintain control over the delivery of the drug. Because of its potential for serious and life-threatening proarrhythmic effects, levomethadyl is reserved for use in the treatment of addicted patients who have no response to other treatments. Levomethadyl is not taken daily; the drug is administered three times a week (Monday/Wednesday/Thursday or uesday/Thursday/
Saturday). Daily use of the usual dose will cause serious overdose.
Methadone, a synthetic narcotic, may be used for the relief of pain, but it also is used in the detoxifi-cation and maintenance treatment of those addicted to narcotics. Detoxification involves withdrawing the patient from the narcotic while preventing withdrawal symptoms.Maintenance therapy is designed to reduce the
patient’s desire to return to the drug that caused addic-tion, as well as to prevent withdrawal symptoms. The dosages used vary with the patient, the length of time the individual has been addicted, and the average amount of drug used each day. Patients enrolled in an outpatient methadone program for detoxification or
maintenance therapy on methadone must continue to receive methadone when hospitalized.

ADVERSE REACTIONS

The adverse reactions differ according to whether the narcotic analgesic acts as an agonist or as an agonistantagonist.
Agonists
One of the major hazards of narcotic administration is respiratory depression, with a decrease in the respira-
tory rate and depth. The most common adverse reactions include light-headedness, dizziness, sedation, constipation, anorexia, nausea, vomiting, and sweating.
When these effects occur, the primary health care provider may lower the dose in an effort to eliminate or
decrease the intensity of the adverse reaction. Other adverse reactions that may be seen with the administration of an agonist narcotic analgesic include:
• Central nervous system—euphoria, weakness,headache, pinpoint pupils, insomnia, agitation,tremor, and impairment of mental and physical tasks
• Gastrointestinal—dry mouth and biliary tractspasms
• Cardiovascular—flushing of the face, peripheral circulatory collapse, tachycardia, bradycardia, and palpitations
• Genitourinary—spasms of the ureters and bladder sphincter, urinary retention or hesitancy
• Allergic—pruritus, rash, and urticaria
• Other—physical dependence, pain at injection site, and local tissue irritation

Agonist-Antagonists
Administration of a narcotic agonist-antagonist may result in symptoms of narcotic withdrawal in those addicted to narcotics. Other adverse reactions associated with the administration of a narcotic agonist antagonist include sedation, nausea, vomiting, sweating, headache,vertigo, dry mouth, euphoria, and dizziness.

CONTRAINDICATIONS

All narcotic analgesics are contraindicated in patients with known hypersensitivity to the drugs. These drugs are contraindicated in patients with acute bronchial asthma, emphysema, or upper airway obstruction and
in patients with head injury or increased intracranial pressure. The drugs are also contraindicated in patients with convulsive disorders, severe renal or hepatic dysfunction, acute ulcerative colitis, and increased intracranial pressure. The narcotic anal-gesics are Pregnancy Category C drugs (oxycodone,Category B) and are not recommended for use during pregnancy or labor (may prolong labor or cause respi-ration depression of the neonate). The use of narcotic analgesics is recommended during pregnancy only if the benefit to the mother outweighs the potential harm to the fetus.

PRECAUTIONS

These drugs are used cautiously in the elderly and in patients with undiagnosed abdominal pain, liver dis-ease, history of addiction to the opioids, hypoxia,supraventricular tachycardia, prostatic hypertrophy, and renal or hepatic impairment. The obese must be monitored closely for respiratory depression while tak-ing the narcotic analgesics. The drug is used cautiously during lactation (wait at least 4 to 6 hours after taking the drug to breastfeed the infant). The narcotics are used cautiously in patients undergoing biliary surgery because the drug may cause spasm of the sphincter of Oddi.

INTERACTIONS

The narcotic analgesics potentiate the central nervous system (CNS) depressant properties of other CNS
depressants, such as alcohol, antihistamines, antide-pressants, sedatives, phenothiazines, and monoamine oxidase inhibitors. Use of the narcotic analgesics within 14 days of the MAO inhibitors may potentiate the effect of either drug. Patients taking the agonist-antagonist narcotic analgesics may experience withdrawal symptoms if the patient has been abusing or using narcotics. The agonist-antagonists drugs can cause opioid with drawal symptoms in those who are physically dependent on the opioids. There is an increased risk of respiratory depression, hypotension, and sedation when narcotic analgesics are administered too soon after barbiturate general anesthesia.

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Unknown Adverse Reactions, Contraindications, Narcotic Analgesics, Uses

Antifungal Drugs Contraindications Precautions And Intrerations

Fungal infections range from superficial skin infections to life-threatening systemic infections. Systemic fungal infections are serious infections that occur when fungi gain entrance into the interior of the body.
A fungus is a colorless plant that lacks chlorophyll.
Fungi that cause disease in humans may be yeastlike or moldlike; the resulting infections are called mycotic
infections or fungal infections.Mycotic (fungal) infections may be one of two types:
1. Superficial mycotic infections
2. Deep (systemic) mycotic infections
The superficial mycotic infections occur on the surface of, or just below, the skin or nails. Superficial infections include tinea pedis (athlete’s foot), tinea cruris (jock itch), tinea corporis (ringworm), onychomycosis (nailfungus), and yeast infections, such as those caused by Candida albicans.
Yeast infections or those caused by C. albicans affect women in the vulvovaginal area and can be difficult
to control. Women who are at increased risk for vulvovaginal yeast infections arethose who have diabetes, are pregnant, or are taking oral contraceptives, antibiotics, or corticosteroids. Deep mycotic infections develop inside the body, such as in the lungs. Treatment for deep mycotic infections is often difficult and prolonged.
ACTIONS
Antifungal drugs may be fungicidal (able to destroy fungi) or fungistatic (able to slow or retard the multiplication of fungi). Amphotericin B (Fungizone IV),miconazole (Monistat), nystatin (Mycostatin), and ketoconazole (Nizoral) are thought to have an effect on the cell membrane of the fungus, resulting in a fungicidal or fungistatic effect. The fungicidal or fungistatic effect of these drugs appears to be related to their concentration in body tissues. Fluconazole (Diflucan) has fungistatic activity that appears to result from the depletion of sterols (a group of substances related to fats) in the fungus cells. Griseofulvin (Grisactin) exerts its effect by being deposited in keratin precursor cells, which are then gradually lost (due to the constant shedding of top skin cells), and replaced by new , noninfected cells.The mode of action of flucytosine (Ancobon) is not clearly understood. Clotrimazole (Lotrimin, Mycelex) binds with phospholipids in the fungal cell membrane,increasing permeability of the cell and resulting in loss of intracellular components.

USES
Antifungal drugs are used to treat superficial and deep fun-gal infections. The antifungal drugs specifically discussed in this chapter are: amphotericin B (Fungizone), flucona-zole (Diflucan), flucytosine (Ancobon), griseofulvin (Grisactin), ketoconazole (Nizoral), and miconazole (Monistat).
Miconazole is an antifungal drug used to treat vulvo-vaginal “yeast” infections and is representative of all of the vaginal antifungal agents.Fungal infections of the skin or mucous membranes may be treated with topical or vaginal preparations.

ADVERSE REACTIONS
When topical antifungal drugs, such as clotrimazole, are applied to the skin or mucous mem-branes, few adverse reactions are seen. On occasion, a local reaction, such as irritation or burning, may occur with topical use. The vulvovaginal antifungal drugs may cause local irritation, redness, stinging, or abdominal
pain. Few adverse reactions are seen with the use of the vulvovaginal antifungal drugs.

Amphotericin B
Amphotericin B is the most effective drug available forthe treatment of most systemic fungal infections.Administration often results in serious reactions,including fever, shaking, chills, headache, malaise, anorexia, joint and muscle pain, abnormal renal func-tion, nausea, vomiting, and anemia. This drug is given
parenterally, usually for a period of several months.Its use is reserved for serious and potentially life-threatening fungal infections. Some of these adverse reactions may be lessened by use of aspirin, antihistamines, or antiemetics.

Fluconazole
Administration may result in nausea, vomiting,headache, diarrhea, abdominal pain, and skin rash.Abnormal liver function tests may be seen and may require follow-up tests to determine if liver function has been affected.
Flucytosine
Administration may result in nausea, vomiting, diar-rhea, rash, anemia, leukopenia, and thrombocytopenia.Signs of renal impairment include elevated blood urea nitrogen (BUN) and
serum creatinine levels. Periodic renal function tests are usually performed during therapy.

Griseofulvin
Administration may result in a hypersensitivity-type reaction that includes rash and urticaria. Nausea, vomit-ing, oral thrush, diarrhea, and headache also may be seen.
Itraconazole
The most common adverse reactions are nausea, vomit-ing, and diarrhea. On occasion, severe hypokalemia (low potassium level) has occurred in patients receiving 600 mg or more of the drug on a daily basis. Hepatotoxicity is a possibility with itraconazole administration.

Ketoconazole
This drug is usually well tolerated, but nausea, vomit-ing, headache, dizziness, abdominal pain, and pruritus may be seen. Most adverse reactions are mild and transient. On rare occasions, hepatic toxicity may be seen,and use of the drug must be discontinued immediately.Periodic hepatic function tests are recommended to monitor for hepatic toxicity.
Miconazole
Administration of miconazole for a vulvovaginal fungal infection may cause irritation, sensitization, or vulvo- vaginal burning. Skin irritation may result in redness, itching, burning, or skin fissures. Other adverse reac-tions with miconazole include cramping, nausea, and headache. Adverse reactions associated with topical use are usually not severe.

CONTRAINDICATIONS, PRECAUTIONS,
AND INTERACTIONS

Amphotericin B

Amphotericin B is contraindicated in patients with a his-tory of allergy to the drug and during lactation. It is used cautiously in patients with renal dysfunction, electrolyte imbalances, and in combination with antineoplastic drugs (because it can cause severe bone marrow sup-pression). This drug is a Pregnancy Category B drug and is used during pregnancy only when the situation is life threatening. When given with the corticosteroids, severe hypokalemia may occur. There may be an increased risk of digitalis toxicity if digoxin is administered con-currently with amphotericin B. Administration with nephrotoxic drugs (eg,aminoglycosides or cyclosporine)may increase the risk of nephrotoxicity in patients also taking amphotericin B. Amphotericin B decreases the effects of miconazole. Amphotericin B is given only under close supervision in the hospital setting.
Fluconazole

Fluconazole is contraindicated in patients with known hypersensitivity to the drug. The drug is used cautiously in patients with renal impairment and during pregnancy (Category C) and lactation. The drug is given during pregnancy only if the benefit of the drug clearly outweighs any possible risk to the infant. When fluconazole is administered with oral hypoglycemics, there is an increased effect of the oral hypoglycemics.Fluconazole may decrease the metabolism of phenytoin and warfarin.

Flucytosine

Flucytosine is contraindicated in patients with known hypersensitivity to the drug. Flucytosine is used autiously in patients with bone marrow depression and with extreme caution in those with renal impairment.
The drug is also used cautiously during pregnancy (Category C) and lactation. When flucytosine and
amphotericin B are administered concurrently, the risk of flucytosine toxicity is increased.

Griseofulvin

Griseofulvin is contraindicated in patients with known hypersensitivity to the drug and in those with severe liver disease. This drug is used cautiously during pregnancy (Category C) and lactation. It is impor-tant to use caution when administering concurrently with penicillin because there is a possibility of crosssensitivity. When griseofulvin is administered with warfarin, the anticoagulant effect may be decreased.When administered with the barbiturates the effect of griseofulvin may be decreased. A decrease in the effects of oral contraceptives may occur with griseo-fulvin therapy, causing breakthrough bleeding, preg-nancy, or amenorrhea. Blood salicylate concentrations may be decreased when the salicylates are adminis tered with griseofulvin.


Itraconazole

Itraconazole is contraindicated in patients with a known hypersensitivity to the drug. The drug is used cautiously in patients with hepatitis, those with human immunodeficiency virus, impaired liver function, and in pregnant women (Pregnancy Category C). In patients with hypochlorhydria, the absorption of itraconazole
is decreased. Multiple drug interactions occur with itraconazole. Itraconazole elevates blood concentrations of digoxin and cyclosporine. Phenytoin decreases blood levels of itraconazole and alters the metabolism of phenytoin. Histamine antagonists, isoniazid, and rifampin decrease plasma levels of itraconazole. There is
an increased anticoagulant effect when warfarin is administered concurrently with itraconazole.

Ketoconazole
Ketoconazole is contraindicated in patients with known hypersensitivity to the drug. Ketoconazole is used cau-tiously in patients with hepatic impairment, those who are pregnant (Category C), and during lactation. The absorption of ketoconazole is impaired when the drug is taken with histamine antagonists and antacids.
Ketoconazole enhances the anticoagulant effect of warfarin and causes an additive hepatotoxicity when given with other hepatotoxic drugs and alcohol.
Administration of ketoconazole with rifampin or isoni-azid may decrease the blood levels of ketoconazole.

Miconazole
Miconazole is contraindicated in patients with known hypersensitivity to the drug. The drug is given cau-tiously in cases of chronic or recurrent candidiasis.With recurrent or chronic candidiasis the patient may have underlying diabetes. Recurrent or chronic candidi-asis requires an evaluation for diabetes. The drug is
used cautiously during pregnancy (Category C). If used during pregnancy, a vaginal applicator may be con-traindicated. Manual insertion of the vaginal tablets may be preferred. Because small amounts of these drugs may be absorbed from the vagina, the drug is used dur-ing the first trimester only when essential.

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Unknown Antifungal Drugs, Contraindications, Intrerations, Precautions