DRUGS Flashcards
Pharmacology
Fluoxetine (Prozac)
Fluoxetine (Prozac) is an anti-depressant and serotonin re-uptake inhibitor (SSRI) that can be used to treat cats for anxiety related disorders at a dose of 0.5 mg/kg orally once daily.
Clorazepate (Tranxene)
Clorazepate is an anti-depressant and benzodiazepine derivative
Alprazolam (Xanax)
Alprazolam is an anti-depressant and benzodiazepine derivative
Clomipramine
Clomipramine is a tricyclic antidepressant. These drugs act, in part, by inhibiting serotonin-norepinephrine re-uptake but they are not selective serotonin re-uptake inhibitors. Side effects include: vomiting, constipation, decreased appetite or anorexia, dry mouth, tachycardia, arrythmia and sedation.
Amitriptyline
Amitriptyline is a tricyclic antidepressant. These drugs act, in part, by inhibiting serotonin-norepinephrine re-uptake but they are not selective serotonin re-uptake inhibitors
Diazepam
Diazepam is a benzodiazepine that is very effective at suppressing seizure activity. IM Diazepam is absorbed very slowly and would not be a good option for an actively seizing cat. Diazepam should be administered rectally in an actively seizing cat. Diazepam can also be used as a premedication and is an appetite stimulant in cats. It is also an anxiolytic and has muscle relaxant effects.
Methocarbamol
Methocarbamol is a muscle relaxant and can be used to control marked tremors or seizures. It is commonly administered to cats after Pyrethrin toxicity which cats are particularly sensitive to.
What is the treatment of Chlamydophila felis?
Causes eye irritation, swelling, tearing, blephorspasm.
Topical tetracycline QID for one week post resolution of clinical signs
Cisapride
Cisapride is a prokinetic drug which may help with intestinal motility.
What gas anesthetic agent will result in the quickest patient recovery?
Sevoflurane. It has a very low blood-gas partition coefficient, meaning that sevoflurane does not readily dissolve in the blood. As a result, the alveolar concentration is close to the same concentration present in the brain, and the concentrations will reach equivalence very rapidly. This is in contrast to ether, which is very soluble in blood, resulting in accumulation of ether in other tissues - this accumulation results in longer times for a patient to fall asleep and waake up.
What drug should never be given to a cat and why?
Acetaminophen. Cats lack glutathione and the enzyme glucoronyl transferase, acetaminophen is metabolized differently. Cats accumulate toxins that result in methemoglobinemia and cell death. The blood becomes dark and the cats become dyspneic and develop facial edema. Immediate gastrointestinal decontamination is needed if the ingestion was within 2-3 hours.
What is the treatment for Acetaminophen toxicity?
N-acetylcysteine, SAMe, vitamin C and supportive care
Mirtazapine
appetite stimulant. Works by antagonizing central pre-synaptic alpha-2 receptors. By antagonizing these receptors, the negative feedback loop that inhibits the release of norepinephrine (NE) is shut down causing an increased build up of NE. Norepinephrine then acts at other receptors to increase appetite. The drug also has antiemetic effects by inhibiting 5HT2 and 5HT3 receptors.
What chemotherpeutic drug causes fatal pulmonary edema?
Cisplatin “cis-plat splats cats”
Praziquantel (Droncit)
Praziquantel is in the products Drontal Plus and Profender. It is approved for the use in cats. This medication is also effective against roundworm, tapeworms and hookworm.
Pyrantel
Treats hookworm and roundworm infections.
Fenbendazole (Panacur)
Treats Taenia taeniaformis, but not Dipylidium caninum. It also treats hookworm, roundworm, and whipworms. Fenbendazole is another treatment option for Giardia, especially for dogs, but efficacy has not been extensively evaluated in cats.
Revolution
Treats and prevents hookworm, roundworm, heartworm, fleas, and ear mites in cats.
Frontline
Treats and prevents fleas and ticks.
Atipamezole (Antisedan)
an alpha-2 antagonist, the reversal agent for medetomidine which is an alpha-2 agonist.
Xylazine
alpha-2 agonist
Yohimbine
an alpha-2 antagonist, a reversel agent for Xylazine
Flumazenil
reversal agent for benzodiazepines
2-pralidoxime
reversal agent for cholinesterase inhibitors
Atenolol
Beta-blocker, used to slow heart rate
Metoprolol
beta-blocker, used to slow heart rate
Diltiazem
Calcium channel blocker, used to slow heart rate
Clopidogrel (Plavix)
used to prevent thromboembolic disease
Furosemide (Lasix)
Loop diuretic, often used in treating CHF.
Enalapril
ACE-inhibitor and does help to decrease blood pressure in some cases by causing vasodilation, but in severe cases of hypertension it can’t adequately control blood pressure.
What is a different condition Enalapril treats?
Other than hypertension.
Protein-losing nephropathy; works by preventing the conversion of angiotensin I to angiotensin II, thus reducing aldosterone concentrations and causing diuresis. It’s dilatory effects on the efferent arterioles of glomeruli help to palliate protein losing nephropathies. It is often used in conjunction with diuretics.
Pimobendan
positive inotrope; a calcium sensitizer that increases cardiac contractility. It is used in cats with DCM.
Levothyroxine
T4 supplementation, used to treat hypothyroidism
Liothyronine
T3 supplementation, used to treat hypothyroidism
What drug/drug class is used to treat heartworm disease in cats?
Corticosteroids, treating with any agent that is an adulticide may potentially result in embolization, release of antigen, and acute death, making this a controversial choice. Corticosteroids work well in reducing inflammation associated with infection and will help alleviate clinical signs.
Treatment: Prednisolone and Heartgard.
Metoclopramide
Prokinetic and anti-emetic drug. The mechanism for its anti-emetic effects is from antagonism of dopamine at its receptors in the chemo-receptor trigger zone of the brain.
Maropitant (Cerenia)
is an anti-emetic. It is a neurokinin-1 inhibitor, which inhibits substance P in the CNS.
Famotidine (Pepcid)
is an H2 receptor blocker, reduces gastric acid secretion.
Omeprazole (Prilosec)
proton pump inhibitor, that reduces gastric acid secretion
Amlodipine
treatment for hypertension. It is a calcium channel blocker and works by preventing calcium influx into vascular smooth muscle cells, thereby causing vasodilation; this relaxes the vessels and allows for reduced blood pressure
Metronidazole
effective at clearing Giardia and reducing cyst shedding of this zoonotic disease. Care should always be taken with metronidazole in kittens due to potential side effects.
What is the treatment for strychnine toxicity?
Methocarbamol; Strychnine is found in some snail baits and other poisons
What treatment is effective against Otodectes infestation (ear mites)?
Milbemycin
What is a side effect of Doxorubicin when it is used in cats?
It causes renal toxicity.
What is a side effect of 5-fluorouracil when used in cats?
It causes neurotoxicity therefore, it should never be used.
What is a side effect of cyclophosphamide when used in dogs?
Sterile hemorrhagic cystitis
What is a side effect of Doxorubicin when used in dogs?
It can cause heart failure
What antibiotic is very poorly absorbed by the feline GI tract?
Sulfadiazine, Clindamycin, Neomycin, Chloramphenicol
Neomycin (aminoglycoside), for this reason it is sometimes used orally to alter intestinal flora without systemic absorption.
What medication is contraindicated in cats with chronic feline bronchial disease (feline asthma)?
Doxycycline, prednisolone, atropine, theophylline
Atropine; because it thickens bronchial secretions and encourages mucous plugging of the airway
Psyllium
a non-fermentable fiber that increases the transit rate of ingesta, increasing the frequency of defecation
How would you treat a cat topically if you found this organism on a fungal culture?
Lime sulfur dip (likely several treatments); the image is a dermatophyte microsporum canis (causes ringworm)
Diltiazem
Calcium channel blocker. Slows the heart by inhibiting the influx of calcium into the myocardial cells. Used to treat Supraventricular tachycardias, hypertrophic cardiomyopathy and hypertension.
What is a potential side effect of administering diethylstillbesterol?
Bone marrow suppression
What drug is commonly used for urinary incontinence in dogs?
Phenylpropanolamine
What drug often causes keratoconjunctivitis sicca as a side effect?
sulfa containing drugs
What is the treatment of choice for transmissible venereal tumor (TVT) in dogs?
Vincristine chemotherapy
What medication is indicated for treatment of DCM in dogs?
a. enalapril
b. prednisone
c. atropine
d. adriamycin
Enalapril; is an ACE-inhibitor which blunts the adverse effects of the renin-angiotensin-aldosterone system thereby reducing sodium and fluid retention. Additionally, ACE-inhibitors cause mild vasodilation by preventing the production of angiotensin-II, which reduces ventricular afterload. Lastly, enalapril and other ACE-inhibitors are protective to cardiac muscle by blunting aldosterone and other hormones which induce cardiac remodeling.
This is an ECG recording of a 9 yr old, MN, Golden that had a bleeding splenic mass surgically removed approximately 4 hours ago. The heart rate is currently 186 bpm. The patient received 0.08 mg/kg of hydromorphone approximately 45 minutes ago. PCV is currently at 24% (normal 33-58%). What is the best treatment option?
a. this is not an alarming hear rate or ECG and requires no treatment
b. The patient is having breakthrough pain due to the low dose of hydromorphone and should be given an adequate dose of hydromorphone
c. this patient is severely anemic and requires a blood transfusion immediately
d. provide a lidocaine bolus followed by a continuous infusion of lidocaine
Provide a lidocaine bolus followed by a continuous infusion of lidocaine; this patient is exhibiting premature ventricular contractions which is commonly observed after splenectomy. Any patient that has a splenectomy should be monitored closely for that reason. Most of the time these are not severe enough to require treatment. There are some general guidlines for when to treat VPCs which include excessive pulse deficits, the patient is clinically affected, a heart rate greater than 180bpm, or greater than 20 second stretch of continuous VPCs.
A 5 yr, F, Weimaraner presents to your clinic with the presenting complaint of cough and difficulty breathing. On exam, the dog is subdued but responsive with a temperature of 103.3F, heart rate of 120bpm, RR of 50bpm. Radiographs are taken. CBC: HCT = 31% (35-57%), neutrophil = 17,275/ul (2,900-12,000/ul), monocyte = 1,484/ul (100-1,400/ul), eosinophil = 630/ul (0-1,300/ul).What is the treatment of choice?
a. oxygen, ampicillin, and enrofloxacin
b. oxygen and furosemide
c. oxygen, acepromazine and hydromorphone
d. oxygen and dexamethasone sodium phosphate
Oxygen, ampicillin, and enrofloxacin; the radiograph represents severe bronchopenumonia. Aggressive broad spectrum antimicrobial therapy with ampicillin and enrofloxacin is the best answer, with supportive care with oxygen as needed. Furosemide and oxygen would be the recommended treatments for a dog with CHF. Sedation and oxygen might be needed for a dog in severe distress from airway obstruction. Corticosteroids would not be an acceptable primary treatment for pneumonia.
This ECG is from a 10 yr, poodle with a history of heart disease that is untreated. She presented for a 3-day history of diarrhea and decreased appetite. On PE, you auscult a grade III/VI murmur and clear lung sounds. There are no pulse deficits. What is the appropriate treatment for this arrhythmia?
a. no anti-arrhythmic therapy is necessary at this time
b. IV injection of furosemide and begin oral administration of furosemide
c. begin oral mexiletine and recheck an ECG strip in 5 days
d. bolus of lidocaine and begin continuous infusion for 12 hours and then try to wean off lidocaine
No anti-arrhythmic at this time; there are several general guidlines/recommendations regarding treatment of VPCs which is what is shown on the ECG strip. These include if the HR is over 180bpm, pulse deficits, clinical signs and VPCs for over 20 seconds in duration. In this case, the HR is not elevated. The PE are not suggesitve of an immediate problem secondary to the arrhythmia. It is recommende that the patient is evaluated regularly and ideally have a consultation with a cardiologist to ensure the progression of heart disease is being minimized.
All of the following drugs are appropriate in the management of tachycardia associated with this arrhythmia in small animal patients except:
a. isoproterenol
b. diltiazem
c. atenolol
d. digoxin
e. procainamide
Isoproterenol; it is a non-specific beta receptor agonist, and will increase the ventricular rate in response to atrial fibrillation, thus is inappropriate in the mangement of this dysrhythmia. The ECG shows atrial fibrillation. Atenolol is a beta-blocker and will slow AV nodal conduction to decrease the ventricular response rate to atrial fibrillation. Procainamide is a class 1A anti-arrhythmic and can be used in aattempts to convert atrial fibrillation to a normal sinus rhythm, though it is rearely effective. Diltiazem is a calcium channel blocker and can be used to slow AV nodal conduction and ventricular response rate. Digoxin will increase vagal tone to the AV node to slow conduction and decrease the heart rate.
A 4yr old, FS, GSD is seen for aggressive chewing and licking at her back legs. After the matted coat is shaved and removed you see the lesions affecting her skin, most severe on her leg. You diagnose deep pyoderma. She is started on a limited ingredient diet, chlorhexidine shampoo, and oral antibiotics. Which oral antibiotic would be best?
a. clindamycin for 4 weeks
b. amoxicillin for 4 weeks
c. cephalexin for 8 weeks
d. trimethoprim-sulfa for 8 weeks
Cephalexin for 8 weeks; deep pyodermas involve tissues deeper than the epidermis, including the dermis and even subcutis. The skin may heal on the surface before the deeper infection is resolved; making clinical cure difficult to assess. In general, deep infection can require 6-8 weeks of antibiotic treatment (and even 12 weeks for severe cases) for resolution. Deep pyoderma can be secondary to allergies, skin fold anomalies, endocrine disorders, immune mediated skin diseases, bacterial and/or fungal skin infections, or migrating foreign bodies. Determining the underlying etiology will help with resolution and minimize chances of treatment failure and re-occurrence. Diagnostics should include skin scraping and impressions, culturing for bacteria and fungi, biopsy, and bloodwork. Treatments typically include antimicrobials that have demonstrated effectiveness, antifungals if needed, and frequent topical treatments with chlorhexidine shampoo and removal of the dead tissue and debris. Incidentally, the GSD are predisposed to severe deep pyodermas that can be difficult to treat. Discussing this with your client will help give them realistic expectations for treatment. GSD are at a higher risk of developing dry eye from Trimethoprim-sulfa; therefore, it is not recommended for this condition due to the length of time required to treat a deep pyoderma.
A 1yr, MN, Boxer presents for lesions on the chin. The chin is mildly painful to the touch, and small papules are present. Biopsy of the area confirms folliculitis and furunculosis. What treatment should be recommended?
a. prednisone
b. clean the area frequently with benzoyl peroxide shampoo or gel
c. instruct the owner to express the papules to decrease the bacterial load
d. recommend switching to plastic food and water bowls since some dogs have reactions to certain metals
clean the area frequently with benxoyl peroxide shampoo or gel; chin acne is a chronic inflammatory disorder of young short coated animals. It is characterized by folliculitis and furunculosis. Secondary bacterial infections can develop if it becomes more advanced. There has been some association seen after contact with plastic water and food bowls, and switching to a different material may help; however, the evidence is more anecdotal and is extrapolated from studies in humans and cats. The chin and lips should be kept as clean as possible with frequent bathing and antibiotic ointment to prevent plugging of the follicles. Some cases can be simply managed by modifying behaviors that can traumatize the chin (chasing balls) and topical antibiotics. Severe cases will need long courses of systemic antibiotics to resolve the infection and then topical corticosteroids to prevent new lesions. The papules should not be expressed, as this can increase inflammation. Benzoyl peroxide is a good choice for a topical antibiotic since it has follicular flushing action.
A 2yr old, FS, Dachshund presents for further evaluation as a result of a mass on the pinna noted by the owner. On PE, the only abnormality noted was this mass. Cytology is consistent with a histiocytoma. Which of the following is the most reasonable treatment option?
a. cryotherapy
b. radiation therapy
c. chemotherapy using lomustine
d. radical surgical excision
e. benign neglect
Benign neglect; histiocytomas are typically benign and will often present as a small, raised mass that may or may not be ulcerated. Fortunately, these masses usually regress on their own, and surgical or medical intervention is typically not necessary.
Which of the following can be recommended for short-term use to treat periodontal disease in dogs?
a. raw hide chews
b. daily chlorhexidine rinses
c. daily periodontal probing
d. enrofloxacin
daily chlorhexidine rinses; daily usage kills off normal bacterial flora in the mouth and will stain the teeth over time. Daily chlorhexidine use is sometimes advocated as a long-term treatment of severe periodontal disease, but alternative therapies should be recommended if possible. Raw hide chews, daily teeth brushing, and chew toys all help to reduce plaque and calculus when used regularly. Enrofloxacin is not a very good choice for oral infections since it is ineffective against anaerobic bacteria. Beta-lactam antibiotics (especially clavamox) or clindamycin are better choices for oral infections because of their activity against anaerobes.
An 8 year old, retired racetrack Greyhound presented for lameness of the right forelimb. Radiographs showed a mixed proliferative and lytic lesion in the region of the proximal humerus. What recommendations will you make to the owners?
a. definitive radiation therapy will need to be instituted at biweekly intervals for the next 6 weeks
b. no treatment is recommended since the blood work is suggestive of metastasis making the prognosis grave
c. coccidiodomycosis was likely acquired at the racetrack and this dog should be started on anti-fungal therapy immediately
d. right forelimb amputation followed by chemotherapy
right forelimb amputation followed by chemotherapy; greyhounds are one of the most predisposed breeds to osteosarcoma. Any geriatric greyhound with lameness should be evaluated promptly for this reason. Unless the patient has a highly suspicious history of living in, or being exposed to areas with high levels of fungal organisms, the radiographic findings are almost confirmatory for osteosarcoma. Regardless of a strong suspcion, core biopsies or needle aspirate of the lesion should be obtained prior to a definitive treatment. The appropriate treatment in dogs without radiographic evidence of metastasis is amputation followed by chemotherapy. Amputation alone will provide an average survival time of 2-6 months, while amputation and chemo will provide 9-12 months. definitive radiation therapy is not possible for these tumors. However, radiation therapy is great when using it as a palliative mode of therapy. The only feature of the blood work which is of note is the ALP. Studies have shown that an elevated ALP is associated with a more aggressive tumor. Aside from informing the owners this potential, it is still recommended to proceed with amputation and chemotherapy. In these situations, some surgeons and oncologists may recommend performing a CT of the chest to evaluate the chest for metastasis more thoroughly prior to proceeding with surgery and chemo.
What is the most appropriate medical treatment for transitional cell carcinoma at the trigone of the bladder, as depicted in the photo?
a. prednisone and combination chemotherapy with cyclophosphamide, vincristine and doxorubicin
b. prednisone and vinblastine or lomustine chemotherapy
c. piroxicam and carboplatin chemotherapy
d. carprofen and combination chemotherapy with cyclophosphamide, vincristine, and doxorubicin
e. clavamox and furosemide
Piroxicam and carboplatin chemotherapy; transitional cell carcinoma of the bladder in dogs can be palliatively managed with non-steroidal anti-inflammatory drugs such as piroxicam. Progression-free interval and survival can be extended with the addition of chemotherapy. The most commonly used agents are carboplatin, cisplatin, and mitoxantrone. Although, cisplatin is effective against TCC, it has increased nephrotoxicity with piroxicam and is less cmmonly used these days in the author’s experience. Secondary infections can be treated with appropriate antibiotics.
This dog presents with a history of PU, PD, weight loss and the ocular changes. Which treatment will be most appropriate for the dogs likely underlying disease?
a. thyroxine
b. amphogel
c. insulin
d. methimazole
e. 0.9% sodium chloride
Insulin; diabetes mellitus is the most likely diagnosis. The classic 4 signs of DM are PU, PD, Polyphagia and weight loss. The dog in this picture has bilateral cataracts. Diabetic cataracts wil occur in most dogs within 6-12 months of diagnosis of diabetes mellitus despite therapy. Diabetic cataracts DO NOT occur in cats. Thyroxine is for hypothyroidism and methimazole is for hyperthyroidism. A sodium chloride infusion could be indicated for a patient presenting with diabetic ketoacidosis, but based on the history, this appears to be a stable diabetic. Amphogel (aluminium hydroxide) is a phosphate binding agent and is not the best choice for treatment of diabetes mellitus.
A 9 yr old, FS, Lab presents for collapse and lethargy. On PE the dog is subdued but responsive with a temp of 100.9F, HR of 170bpm, RR of 40brpm. Chest radiographs are below. A CBC shows a HCT of 41% (35-57%), neutrophil count of 6,275/ul (2,900-12,000/ul), monocyte count of 948/ul (100-1,400/ul) and eosinophil count of 630/ul (0-1,300/ul). What is the treatment of choice?
a. Furosemide
b. Pericardiocentesis
c. Broad spectrum antibiotics
d. Melarsomine
e. Terbutaline
Pericardiocentesis; the radiograph and case are a good example of pericardial effusion with the classic finding of a markedly enlarged heart with a globoid shape. The most common type of effusion by far is hemorrhage which can be idiopathic or from neoplasia such as hemangiosarcoma. Based on this finding, in conjunction with the dog’s tachycardia, a pericaardial tap for both diagnostic and therapeutic purooses is indicated. Furosemide is contraindicated in cases of pericardial effusion because it will decreased preload in the right side of the heart and can promote circulatory failure. Melarsomine is the treatment for heartworm. Antibiotics are very unlikely to help this dog unless the effusion is from some sort of infectious pericarditis, which would be extremely unusual in dogs.
A 3 yr old Thoroughbred gelding just completed a race and has discharge from it’s nostrils. What would be an appropriate treatment for this horse prior to the next race?
a. vasopressin
b. furosemide
c. plasma transfusion to replace clotting factors
d. whole blood transfusion
e. vitamin K
Furosemide; the discharge is blood with the most likely diagnosis being exercise-induced pulmonary hemorrhage (EIPH). One of the most commonly administered medications for EIPH is furosemide, which seems to decrease the incidence or lessen the severity of bleeding. The exact mechanism by which this occurs is not completely known but may be associated with reduced pulmonary capillary pressure.
A 15 year old mare is diagnosed with mild acute laminitis. What treatment can be used for this horse?
a. Trimethoprim sulfa
b. Phenoxybenzamine
c. Application of horse shoes
d. Prednisone
Phenoxybenzamine; this is an alpha-adrenergic antagonist promoting vasodilation and restoration of blood flow to the digits. Prednisone is contraindicated in laminitis because corticosteroids are believed to induce the condition. Antibiotics are not indicated unless a secondary bacterial infection develops. Application of a horse shoe would not help and would be very painful in an already sensitive and painful condition. Other medications used to restore blood flow to the digits include acepromazine, isoxsuprine hydrochloride, dimethylsulfoxide (DMSO), heparin, and nitroglycerine.
