Relative contraindications

Relative contraindications to the use of anticholinesterase treatment include a history of cardiovascular disease, asthma, glaucoma, and gastrointestinal or genitourinary obstruction. Symptomatic treatment of tachyarrhythmias with propranolol may be considered P blockers, however, are less effective than physostigmine. 

This product is also only available by prescription. The recommended treatment period is up to 24 weeks (McNeil Consumer Products 1997). Using the inhaler by puffing 80 deep inhalations over 20 minutes results in a systemic absorption through the buccal mucosa of 2 mg of nicotine, with maximal nicotine concentrations occurring 15 minutes after the end of inhalation. When the product is used as directed, the patient will likely use 6-16 inhalers per day. This form of NRT is relatively contraindicated in patients with asthma because, although most of the nicotine is absorbed through the buccal mucosa and it is not delivered to the lungs (McNeil Consumer Products 1997), nicotine by inhalation may produce bronchial constriction. 

INR > 1.7 (PT > 15 if no INR available) with or without chronic oral anticoagulant use Seizure at onset of stroke (This relative contraindication is intended to prevent treatment of patients with a deficit due to postictal Todd s paralysis or with seizure due to some other CNS lesion that precludes thrombolytic therapy. If rapid diagnosis of vascular occlusion can be made, treatment may be given.)... 

If a stroke patient receives intravenous (IV) thrombolysis, care often continues in the ED until the patient arrives in the ICU. Close monitoring must continue during this time, with special attention to the blood pressure. The blood pressure is most commonly checked via an arm cuff, since the placement of invasive lines (e.g., arterial catheterization) is relatively contraindicated once the patient has received intravenous thrombolysis (unless the situation is emergent and mandates such treatment). The systolic pressure must not exceed 185 mm Hg, and the diastolic pressure limit should be 110 mm Hg. Should the blood pressure exceed these limits, IV antihypertensive agents should be administered. IV pushes of labetolol (10-20 mg over 1-2 minutes) may be effective, but if patients are refractory to these initial measures then a continuous infusion of labetolol (0.5-2.0 mg/minute), nicardipine (5-15 mg/hour), or nitro-prusside (0.25-10 mg/kg/minute) may be necessary to keep the patient s blood pressure within the range. There will be a more detailed discussion of these antihypertensive agents, including their side effect profiles, later in this chapter. 

Despite their clear benefits, ACE inhibitors are still underutilized in HF. One reason is undue concern or confusion regarding absolute versus relative contraindications for their use. Absolute contraindications include a history of angioedema, bilateral renal artery stenosis, and pregnancy. Relative contraindications include unilateral renal artery stenosis, renal insufficiency, hypotension, hyperkalemia, and cough. Relative contraindications provide a warning that close monitoring is required, but they do not necessarily preclude their use. 

Blockers are contraindicated in patients with severe bradycardia (heart rate less than 50 beats per minute) or AV conduction defects in the absence of a pacemaker. (3-Blockers should be used with particular caution in combination with other agents that depress AV conduction (e.g., digoxin, verapamil, and diltiazem) because of increased risk for bradycardia and heart block. Relative contraindications include asthma, bronchospastic disease, severe depression, and peripheral vascular disease. (3,-Selective blockers are preferred in patients with asthma or chronic obstructive pulmonary... 

Significant closed head or facial trauma within 3 months Relative Contraindications... 

The P-blockers propranolol and timolol are FDA-approved for migraine prophylaxis, but other drugs in the class are also as effective.46 Cautious dosage titration is advised for those patients who do not have other indications for P-blocker use. Rizatriptan interacts with propranolol and thus dosages must be titrated downward, or another triptan chosen for abortive therapy.36 Comorbid reactive airway disease is a relative contraindication to P-blocker prophylaxis, and patients with cardiac conduction disturbances should be closely monitored. Calcium channel antagonists are often used when patients cannot tolerate P-blockers. They are purported to beneficially... 

Disulfiram works by irreversibly blocking the enzyme aldehyde dehydrogenase, a step in the metabolism of alcohol, resulting in increased blood levels of the toxic metabolite acetaldehyde. As levels of acetaldehyde increase, the patient experiences decreased blood pressure, increased heart rate, chest pain, palpitations, dizziness, flushing, sweating, weakness, nausea and vomiting, headache, shortness of breath, blurred vision, and syncope. These effects are commonly referred to as the disulfiram-ethanol reaction. Their severity increases with the amount of alcohol that is consumed, and they may warrant emergency treatment. Disulfiram is contraindicated in patients who have cardiovascular or cerebrovascular disease, because the hypotensive effects of the disulfiram-alcohol reaction could be fatal in such patients or in combination with antihypertensive medications. Disulfiram is relatively contraindicated in patients with diabetes, hypothyroidism, epilepsy, liver disease, and kidney disease as well as impulsively suicidal patients. 

Discuss the risks associated with the use of contraceptives, and state absolute and relative contraindications to their use. 

Cephalexin is considered safe and effective. Nitrofurantoin should not be used after week 37 due to concern for hemolytic anemia in the newborn. Sulfa-containing drugs may increase risk for kernicterus in the newborn and should be avoided during the last weeks of gestation. Folate antagonists, such as trimethoprim, are relatively contraindicated during the first trimester because of their association with cardiovascular malformations. Fluoroquinolones and tetracyclines are contraindicated. 

For penicillin-allergic adults, use a fluoroquinolone (ciprofloxacin 0.5-0.75 g orally every 12 hours or 0.4 g IV every 12 hours levofloxacin 0.5-0.75 g orally or IV every 24 hours or moxifloxacin 0.4 g orally or IV every 24 hours). eGentamicin or tobramycin, 2 mg/kg loading dose, then maintenance dose as determined by serum concentrations, fluoroquinolone or aztreonam 1 g IV every 6 hours may be used in place of the aminoglycoside in patients with severe renal dysfunction or other relative contraindications to aminoglycoside use. 

High-potency benzodiazepines (e.g., clonazepam and lorazepam) are common alternatives to or in combination with antipsychotics for acute mania, agitation, anxiety, panic, and insomnia or in those who cannot take mood stabilizers. Lorazepam IM may be used for acute agitation. A relative contraindication for long-term benzodiazepines is a history of drug or alcohol abuse or dependency. 

The quinolones are relatively contraindicated in pregnant women and children as animal studies have... 

Its most important adverse effects are visual disturbances. This ocular toxicity is dose dependent and has an incidence of lower than 1 % at low doses but can reach 5% at high dose regimens. Ocular toxicity manifests itself as retrobulbar neuritis usually after the second month of use. If therapy is discontinued immediately it is mostly reversible but not always. During the treatment visual function should periodically be tested. Age under 8 years is a relative contraindication as visual symptoms are difficult to monitor. 

Because of its anticholinergic properties, disopyramide should not be used in patients with glaucoma. Urinary retention and benign prostatic hypertrophy are also relative contraindications to disopyramide therapy. Patients with myasthenia gravis may have a myasthenic crisis after disopyramide administration as a result of the drug s local anesthetic action at the neuromuscular junction. The elderly patient may exhibit increased sensitivity to the anticholinergic actions of disopyramide. 

B. Anticholinergic agents, such as procainamide and disopyramide, are relatively contraindicated in patients with glaucoma. Procainamide is hypotensive rather than hypertensive. The local anesthetic activity of procainamide would have no adverse interaction with the diabetes mellitus. 

The contraindications to the use of thrombolytic drugs are similar to those for the anticoagulant drugs. Absolute contraindications include active bleeding, cardiopulmonary resuscitation (trauma to thorax is possible), intracranial trauma, vascular disease, and cancer. Relative contraindications include uncontrolled hypertension, earlier central nervous system surgery, and any known bleeding risk. 

Because of the potential for hematological and hepatic toxicity, carbamazepine should not be administered to patients with liver disease or thrombocytopenia or to those at risk for agranulocytosis. For this reason, carbamazepine is strictly contraindicated in patients receiving clozapine. Because of reports of teratogenicity, including increased risks of spina bifida (Rosa 1991), microcephaly (Bertol-lini et al. 1987), and craniofacial defects (Jones et al. 1989), carbamazepine is relatively contraindicated in pregnant women. Pretreatment evaluation should include a complete blood count and determination of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. 

The APA Task Force Report on ECT supports the concept of differing levels of relative contraindications and no longer lists absolute restrictions for the... 

Relative contraindications to the use of BZDs concern patients with a history of the following ... 

Because CBZ is metabolized via the liver, this constitutes a relative contraindication in patients with hepatic dysfunction. Therefore, LFTs should be obtained before initiating CBZ therapy and monitored regularly every 6 to 12 months. Sustained LFT levels usually warrant the withdrawal of CBZ. 

Inhibitors of the renal cation secretion mechanism, eg, cimetidine, prolong the half-life of dofetilide. Since the QT-prolonging effects and risks of ventricular proarrhythmia are directly related to plasma concentration, dofetilide dosage must be based on the estimated creatinine clearance. Treatment with dofetilide should be initiated in hospital after baseline measurement of the rate-corrected QT interval (QTC) and serum electrolytes. A baseline QTC of > 450 ms (500 ms in the presence of an intraventricular conduction delay), bradycardia of < 50 bpm and hypokalemia are relative contraindications to its use. 

Monoamine oxidase inhibitors Relative contraindication to all opioid analgesics because of the high incidence of hyperpyrexic coma hypertension has also been reported. 

Pain at the injection site is common but usually not severe. The most serious toxic effect with streptomycin is disturbance of vestibular function—vertigo and loss of balance. The frequency and severity of this disturbance are in proportion to the age of the patient, the blood levels of the drug, and the duration of administration. Vestibular dysfunction may follow a few weeks of unusually high blood levels (eg, in individuals with impaired renal function) or months of relatively low blood levels. Vestibular toxicity tends to be irreversible. Streptomycin given during pregnancy can cause deafness in the newborn and therefore is relatively contraindicated. 

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