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People with erectile dysfunction (ED) use Sildenafil (brand name: Viagra) or other ED drugs (Vardenafil, Tadalafil, etc.) This is for sexual disorder relief, but when it comes to Sildenafil for dogs, the drug is used not for sexual dysfunctions.
The ff. disorders are treated with Sildenafil:
- Pulmonary hypertension (increased blood pressure in lung arteries)
- Blood clot
Sildenafil treatment for dogs is intended to induce vasodilation, that is, relaxation of parts within arteries or blood vessels. The increased dilation results in more blood inflow through blood vessels.
Pulmonary Hypertension
Pulmonary hypertension in dogs is characterized by excessive blood flow in the capillaries of the lungs. The capillaries in the lungs are small branches of blood vessels, and they receive oxygenated blood pumped by the heart.
In this condition, the heart’s ventricles are also affected – the left ventricle becomes filled with high amounts of blood, while the right ventricle becomes enlarged.
This being the overall scenario of the heart and the lungs, the body receives low amounts of oxygenated blood, resulting in symptoms, including:
- Exercise intolerance
- Difficulty breathing
- Blue-purple colored skin
In due time, other symptoms will develop:
- Coughing (excessive coughing can result to release of blood through the mouth)
- Fainting
- Fatigue
- Weight loss
- Enlarged abdomen
Causes of Pulmonary Hypertension
The excess pressure happening in the heart and the lungs is caused by an underlying condition. Your veterinarian will run tests to determine if your pet has:
- Cancer
- Pneumonia
- Bronchitis
- Thrombosis (blood clot in the lungs)
- Blood vessel blockage
- Adult respiratory distress syndrome
We include the causes and symptoms of pulmonary hypertension so you can be ready with details to tell your vet for faster diagnosis, and whether or not your pet can receive treatment for dogs using Viagra.
Megaesophagus Treated with Viagra for Dogs
Another disease where veterinarians give Sildenafil prescription for dogs is megaesophagus or enlargement of the esophagus.
Such an enlargement causes low esophageal motility. Motility in the esophagus is required, as this is the way the body moves food and liquid down the stomach.
Symptoms include vomiting, nasal discharge, cough, and weight loss. Causes of megaesophagus in dogs include:
- Parasitic infection
- Toxicity
- Esophageal inflammation
- Foreign body stuck in the esophagus
- Tumor in the esophagus
- Neuromuscular disease
The effectiveness of using oral sildenafil citrate for dogs with megaesophagus is demonstrated in this study.
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Congestive Heart Failure in Dogs
Symptoms of congestive heart failure (CHF) in dogs can also be treated with Viagra. The condition is characterized by the inability of the heart to pump an adequate amount of blood for the body.
The most common causes of CHF are:
- Dilated cardiomyopathy – the left ventricle of the heart is enlarged and weakened
- Mitral valve insufficiency – the mitral valve of the heart does not properly close after the heart pumps out blood
The most common clinical signs for CHF in dogs are:
- Persistent coughing
- Difficulty breathing
Dosage Information
In Viagra treatment for dogs, 1-3 milligrams can be given two to three times per 24 hours. Improvement of symptoms can be noted within 48 – 72 hours.
In a particular study, where dogs showed symptoms of collapse, respiratory distress, cough, and temporary loss of consciousness, the median dosage was 1.9 mg/kg.
Two things are essential when identifying the right dosage – the weight of the dog and the severity of the condition or symptoms. The vet will determine the time to stop the medication.
In another study, the researchers experimented with a dosage of 1 mg minimum and 4 mg maximum.
Be very strict in following your vet’s prescription on Sildenafil for dogs’ dosage, as there are side effects associated with this drug, and there were cases of overdose that were reported.
Side Effects
Two side effects to take note of dogs’ Sildenafil treatment:
- Gastrointestinal upset
- Reddening of the skin
Nature.com is one of their articles took note of the following symptoms, which they say are typically associated with the vasodilatory effect of the drug:
- Visual disturbance = change in vision that indicates abnormal function. It can also be a sign of stroke.
- Headache
- Dyspepsia – discomfort or pain in the upper abdomen
- Tachycardia – rapid heart rate
In a 7-month old puppy, Sildenafil was administered for pulmonary hypertension. Exercise capacity, heart murmur, dyspnea, and cyanosis were improved after four months of therapy.
After four years, the researcher conducted an assessment and reported that with follow-up Viagra dogs’ treatment, the dog showed an excellent quality of life WITHOUT SIDE EFFECTS.
Is It Safe?
Years of research and in the actual administration of Sildenafil in patients, the general notion of safety has been established, not only with dogs and cats but also with people.
A couple of reminders must be noted to maintain safety and prevent adverse reactions:
- The drug should not be placed where children can reach it. It should only be given to the pet for which it was prescribed.
- Federal law restricts the use of Sildenafil on the order of a licensed vet only. Dogs with heart and lung problems and those experiencing blood or fluid loss, shock, and low blood pressure should not use this drug.
Drug Interactions of Viagra for Dog Treatment
Drugs that can lower blood pressure should not be used together with Sildenafil.
Lower blood pressure is a side effect of Viagra, and if used with drugs with the same effect, Viagra can make the blood pressure too low, and that can be fatal for your dog.
Here are those drugs:
- Amlodipine
- Alpha-adrenergic blockers
- nitroprusside sodium
Viagra interacts with the ff:
- Rifampin
- Phenobarbital
- Itraconazole
- Ketoconazole
- Clarithromycin
- Erythromycin
- Cimetidine
It is also crucial that you discuss with your vet for the possibility of the pet to be suffering from kidney or liver failure.
In people, these conditions are considered, and patients with these conditions receive low doses of Sildenafil to protect them from fatal consequences.
For dogs with these conditions, consider other treatment methods such as those that can remove excess fluid in the lungs, or oxygen therapy or medications that can dilate the breathing passages.
For questions on Sildenafil for dogs and other treatment methods, feel free to post them below. We will get to these questions and give you answers the best that we can.
