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Can you take Doxazosin with Viagra?

1 drug interaction and 33 additional warnings found for the following 2 drugs:

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Drug interactions

Moderate drug interactions

Moderate:

doxazosin sildenafil

Applies to: doxazosin and Viagra (sildenafil)

Talk to your doctor before using sildenafil together with doxazosin. Combining these medications can lower your blood pressure and increase the risk of dizziness, lightheadedness, fainting, flushing, headache, and nasal congestion. These side effects may also occur with either medication alone and are most likely to be seen at the beginning of treatment, following a dose increase, or when treatment is restarted after an interruption. Let your doctor know if you develop these symptoms and they do not go away after a few days or they become troublesome. Avoid driving or operating hazardous machinery until you know how these medications affect you, and use caution when getting up from a sitting or lying position. In general, your blood pressure should be stable and you should be on a steady dose of one medication before you begin the other. You may need a dose adjustment or your blood pressure checked more often if you take both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Food/lifestyle interactions

Moderate food/lifestyle interactions

Moderate:

sildenafil Food/Lifestyle

Applies to: Viagra (sildenafil)

If you are receiving therapy with sildenafil you should avoid the regular consumption of large amounts of grapefruits and grapefruit juice. Grapefruit can raise the levels of sildenafil in your body and delay the time it takes for the medication to work. Do not increase or decrease the amount of grapefruit products in your diet without first talking to your doctor.

Moderate:

doxazosin Alcohol (Ethanol)

Applies to: doxazosin

Ask your doctor before using doxazosin together with ethanol (alcohol). Using doxazosin with ethanol (alcohol) can lower your blood pressure. This can cause dizziness or feeling like you might pass out, especially when getting up from a sitting or lying position. This may be more likely to occur when you first start taking either of these medications. You may need a dose adjustment or need your blood pressure checked more often if you take both medications. You may develop flushing, warmth or redness under your skin or tingly feeling after alcohol intake (especially in you are of Asian descent) and should be advised to avoid alcohol or limit your intake. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Disease interactions

31 potential interactions Applies to: 28 conditions, including Seizures, Diarrhea, Hypotension, Tinnitus, and Peptic Ulcer.

Alcoholism

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Alcoholism.

Alcohol consumption may intensify the pressure-lowering effects of mild vasodilators, such as phosphodiesterase 5 (PDE5) inhibitors. Therefore, patients that consume alcohol should be warned to limit alcohol intake while receiving these agents.

Autonomic Neuropathy

Moderate:

doxazosin

Doxazosin has a moderate potential interaction with Autonomic Neuropathy.

Peripheral alpha 1- adrenergic receptor blocking agents (aka alpha 1- blockers) cause vasodilation and can produce marked hypotension, especially orthostatic hypotension with syncope or other postural symptoms such as dizziness, lightheadedness, and palpitations. Orthostatic effects are most common during initiation of therapy and often occur within 90 minutes after the first dose. However, they can also occur following a dosage increase or resumption of therapy after an interruption of more than a few days. Agents with alpha 1a specificity, such as tamsulosin, act primarily on the prostate but are not devoid of hypotensive effects. Therapy with peripheral alpha-1 blockers should be administered cautiously in patients with or predisposed to hypotensive or syncopal episodes. Caution is also advised in patients who are dehydrated (e.g., due to severe or prolonged diarrhea or vomiting), since they may be more sensitive to the hypotensive effect of the drugs. Therapy should be initiated with the lowest dosage possible and titrated gradually based on patient response and tolerance in accordance with the individual product package labeling. During initiation or reinstitution of therapy and following an increase in dosage, patients should be advised not to rise abruptly from a sitting or recumbent position and to avoid situations where injury could result if syncope occur. Concomitant use of alcohol, extensive periods of standing, prolonged or intense exercise, and exposure to heat can also precipitate orthostatic hypotension and should be minimized. If dizziness, lightheadedness or palpitations occur, the patient should sit or lie down, and seek medical attention if symptoms are recurrent or bothersome.

Biliary Obstruction

Moderate:

doxazosin

Doxazosin has a moderate potential interaction with Biliary Obstruction.

Doxazosin is metabolized by the liver and subsequently excreted in the bile, primarily as metabolites, some of which are pharmacologically active. In patients with cirrhosis (Child-Pugh Class A) given a single 2 mg dose, there was a 40% increase in exposure to doxazosin compared to patients with normal hepatic function. The clearance was reduced by 30%, while elimination half-life was not significantly changed. Therapy with doxazosin should be administered cautiously in patients with significantly impaired hepatic or biliary function, since drug and/or metabolite accumulation may occur.

Bleeding Associated with Coagulation Defect

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Bleeding Associated with Coagulation Defect.

The safety of sildenafil in patients with bleeding disorders or active peptic ulceration is unknown. In clinical studies, the incidence of bleeding (i.e., epistaxis) was increased in patients with pulmonary arterial hypertension secondary to connective tissue disease and in patients on concomitant therapy with an oral vitamin K antagonist. There have been postmarketing reports of bleeding events in patients treated with sildenafil for erectile dysfunction.

Bleeding Disorder

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Bleeding Disorder.

The safety of sildenafil in patients with bleeding disorders or active peptic ulceration is unknown. In clinical studies, the incidence of bleeding (i.e., epistaxis) was increased in patients with pulmonary arterial hypertension secondary to connective tissue disease and in patients on concomitant therapy with an oral vitamin K antagonist. There have been postmarketing reports of bleeding events in patients treated with sildenafil for erectile dysfunction.

Cardiovascular Conditions and Disorders

Major:

Viagra

The sildenafil in Viagra has a major potential interaction with Cardiovascular Conditions and Disorders.

The use of phosphodiesterase-5 (PDE5) inhibitors is not recommended in patients with preexisting cardiovascular disease for whom sexual activity is inadvisable due to the potential cardiac risk. Physicians should also consider the vasodilatory effect of these drugs and whether they may adversely affect patients with underlying cardio- and/or cerebrovascular conditions, in particular those who have suffered a myocardial infarction, stroke, or life-threatening arrhythmia within the last 6 months; those with resting hypotension (BP < 90/50) or hypertension (BP > 170/110); and those with unstable angina associated with cardiac failure or coronary artery disease. There are no controlled clinical data on the safety or efficacy in such patients. Other adverse cardiovascular effects reported include angina pectoris, myocardial infarction, AV block, ventricular arrhythmia, tachycardia, palpitation, hypotension, postural hypotension, syncope, cerebral thrombosis, cerebrovascular hemorrhage, transient ischemic attack, cardiac arrest, heart failure, and hypertension. Many of these events occurred in patients with cardiovascular risk factors and during or shortly after sexual activity.

Cerebral Vascular Disorder

Major:

Viagra

The sildenafil in Viagra has a major potential interaction with Cerebral Vascular Disorder.

The use of phosphodiesterase-5 (PDE5) inhibitors is not recommended in patients with preexisting cardiovascular disease for whom sexual activity is inadvisable due to the potential cardiac risk. Physicians should also consider the vasodilatory effect of these drugs and whether they may adversely affect patients with underlying cardio- and/or cerebrovascular conditions, in particular those who have suffered a myocardial infarction, stroke, or life-threatening arrhythmia within the last 6 months; those with resting hypotension (BP < 90/50) or hypertension (BP > 170/110); and those with unstable angina associated with cardiac failure or coronary artery disease. There are no controlled clinical data on the safety or efficacy in such patients. Other adverse cardiovascular effects reported include angina pectoris, myocardial infarction, AV block, ventricular arrhythmia, tachycardia, palpitation, hypotension, postural hypotension, syncope, cerebral thrombosis, cerebrovascular hemorrhage, transient ischemic attack, cardiac arrest, heart failure, and hypertension. Many of these events occurred in patients with cardiovascular risk factors and during or shortly after sexual activity.

Dehydration

Moderate:

doxazosin

Doxazosin has a moderate potential interaction with Dehydration.

Peripheral alpha 1- adrenergic receptor blocking agents (aka alpha 1- blockers) cause vasodilation and can produce marked hypotension, especially orthostatic hypotension with syncope or other postural symptoms such as dizziness, lightheadedness, and palpitations. Orthostatic effects are most common during initiation of therapy and often occur within 90 minutes after the first dose. However, they can also occur following a dosage increase or resumption of therapy after an interruption of more than a few days. Agents with alpha 1a specificity, such as tamsulosin, act primarily on the prostate but are not devoid of hypotensive effects. Therapy with peripheral alpha-1 blockers should be administered cautiously in patients with or predisposed to hypotensive or syncopal episodes. Caution is also advised in patients who are dehydrated (e.g., due to severe or prolonged diarrhea or vomiting), since they may be more sensitive to the hypotensive effect of the drugs. Therapy should be initiated with the lowest dosage possible and titrated gradually based on patient response and tolerance in accordance with the individual product package labeling. During initiation or reinstitution of therapy and following an increase in dosage, patients should be advised not to rise abruptly from a sitting or recumbent position and to avoid situations where injury could result if syncope occur. Concomitant use of alcohol, extensive periods of standing, prolonged or intense exercise, and exposure to heat can also precipitate orthostatic hypotension and should be minimized. If dizziness, lightheadedness or palpitations occur, the patient should sit or lie down, and seek medical attention if symptoms are recurrent or bothersome.

Diarrhea

Moderate:

doxazosin

Doxazosin has a moderate potential interaction with Diarrhea.

Peripheral alpha 1- adrenergic receptor blocking agents (aka alpha 1- blockers) cause vasodilation and can produce marked hypotension, especially orthostatic hypotension with syncope or other postural symptoms such as dizziness, lightheadedness, and palpitations. Orthostatic effects are most common during initiation of therapy and often occur within 90 minutes after the first dose. However, they can also occur following a dosage increase or resumption of therapy after an interruption of more than a few days. Agents with alpha 1a specificity, such as tamsulosin, act primarily on the prostate but are not devoid of hypotensive effects. Therapy with peripheral alpha-1 blockers should be administered cautiously in patients with or predisposed to hypotensive or syncopal episodes. Caution is also advised in patients who are dehydrated (e.g., due to severe or prolonged diarrhea or vomiting), since they may be more sensitive to the hypotensive effect of the drugs. Therapy should be initiated with the lowest dosage possible and titrated gradually based on patient response and tolerance in accordance with the individual product package labeling. During initiation or reinstitution of therapy and following an increase in dosage, patients should be advised not to rise abruptly from a sitting or recumbent position and to avoid situations where injury could result if syncope occur. Concomitant use of alcohol, extensive periods of standing, prolonged or intense exercise, and exposure to heat can also precipitate orthostatic hypotension and should be minimized. If dizziness, lightheadedness or palpitations occur, the patient should sit or lie down, and seek medical attention if symptoms are recurrent or bothersome.

Hearing Loss

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Hearing Loss.

Use of phosphodiesterase-5 (PDE5) inhibitors has been associated with sudden decrease or loss of hearing, which may be accompanied by tinnitus or dizziness. Patients with hearing problems should stop taking these agents and seek prompt medical care.

History - Cerebrovascular Disease

Major:

Viagra

The sildenafil in Viagra has a major potential interaction with History - Cerebrovascular Disease.

The use of phosphodiesterase-5 (PDE5) inhibitors is not recommended in patients with preexisting cardiovascular disease for whom sexual activity is inadvisable due to the potential cardiac risk. Physicians should also consider the vasodilatory effect of these drugs and whether they may adversely affect patients with underlying cardio- and/or cerebrovascular conditions, in particular those who have suffered a myocardial infarction, stroke, or life-threatening arrhythmia within the last 6 months; those with resting hypotension (BP < 90/50) or hypertension (BP > 170/110); and those with unstable angina associated with cardiac failure or coronary artery disease. There are no controlled clinical data on the safety or efficacy in such patients. Other adverse cardiovascular effects reported include angina pectoris, myocardial infarction, AV block, ventricular arrhythmia, tachycardia, palpitation, hypotension, postural hypotension, syncope, cerebral thrombosis, cerebrovascular hemorrhage, transient ischemic attack, cardiac arrest, heart failure, and hypertension. Many of these events occurred in patients with cardiovascular risk factors and during or shortly after sexual activity.

History - Myocardial Infarction

Major:

Viagra

The sildenafil in Viagra has a major potential interaction with History - Myocardial Infarction.

The use of phosphodiesterase-5 (PDE5) inhibitors is not recommended in patients with preexisting cardiovascular disease for whom sexual activity is inadvisable due to the potential cardiac risk. Physicians should also consider the vasodilatory effect of these drugs and whether they may adversely affect patients with underlying cardio- and/or cerebrovascular conditions, in particular those who have suffered a myocardial infarction, stroke, or life-threatening arrhythmia within the last 6 months; those with resting hypotension (BP < 90/50) or hypertension (BP > 170/110); and those with unstable angina associated with cardiac failure or coronary artery disease. There are no controlled clinical data on the safety or efficacy in such patients. Other adverse cardiovascular effects reported include angina pectoris, myocardial infarction, AV block, ventricular arrhythmia, tachycardia, palpitation, hypotension, postural hypotension, syncope, cerebral thrombosis, cerebrovascular hemorrhage, transient ischemic attack, cardiac arrest, heart failure, and hypertension. Many of these events occurred in patients with cardiovascular risk factors and during or shortly after sexual activity.

Hypotension

Major:

Viagra

The sildenafil in Viagra has a major potential interaction with Hypotension.

The use of phosphodiesterase-5 (PDE5) inhibitors is not recommended in patients with preexisting cardiovascular disease for whom sexual activity is inadvisable due to the potential cardiac risk. Physicians should also consider the vasodilatory effect of these drugs and whether they may adversely affect patients with underlying cardio- and/or cerebrovascular conditions, in particular those who have suffered a myocardial infarction, stroke, or life-threatening arrhythmia within the last 6 months; those with resting hypotension (BP < 90/50) or hypertension (BP > 170/110); and those with unstable angina associated with cardiac failure or coronary artery disease. There are no controlled clinical data on the safety or efficacy in such patients. Other adverse cardiovascular effects reported include angina pectoris, myocardial infarction, AV block, ventricular arrhythmia, tachycardia, palpitation, hypotension, postural hypotension, syncope, cerebral thrombosis, cerebrovascular hemorrhage, transient ischemic attack, cardiac arrest, heart failure, and hypertension. Many of these events occurred in patients with cardiovascular risk factors and during or shortly after sexual activity.

Moderate:

doxazosin

Doxazosin has a moderate potential interaction with Hypotension.

Peripheral alpha 1- adrenergic receptor blocking agents (aka alpha 1- blockers) cause vasodilation and can produce marked hypotension, especially orthostatic hypotension with syncope or other postural symptoms such as dizziness, lightheadedness, and palpitations. Orthostatic effects are most common during initiation of therapy and often occur within 90 minutes after the first dose. However, they can also occur following a dosage increase or resumption of therapy after an interruption of more than a few days. Agents with alpha 1a specificity, such as tamsulosin, act primarily on the prostate but are not devoid of hypotensive effects. Therapy with peripheral alpha-1 blockers should be administered cautiously in patients with or predisposed to hypotensive or syncopal episodes. Caution is also advised in patients who are dehydrated (e.g., due to severe or prolonged diarrhea or vomiting), since they may be more sensitive to the hypotensive effect of the drugs. Therapy should be initiated with the lowest dosage possible and titrated gradually based on patient response and tolerance in accordance with the individual product package labeling. During initiation or reinstitution of therapy and following an increase in dosage, patients should be advised not to rise abruptly from a sitting or recumbent position and to avoid situations where injury could result if syncope occur. Concomitant use of alcohol, extensive periods of standing, prolonged or intense exercise, and exposure to heat can also precipitate orthostatic hypotension and should be minimized. If dizziness, lightheadedness or palpitations occur, the patient should sit or lie down, and seek medical attention if symptoms are recurrent or bothersome.

Liver Disease

Moderate:

doxazosin

Doxazosin has a moderate potential interaction with Liver Disease.

Doxazosin is metabolized by the liver and subsequently excreted in the bile, primarily as metabolites, some of which are pharmacologically active. In patients with cirrhosis (Child-Pugh Class A) given a single 2 mg dose, there was a 40% increase in exposure to doxazosin compared to patients with normal hepatic function. The clearance was reduced by 30%, while elimination half-life was not significantly changed. Therapy with doxazosin should be administered cautiously in patients with significantly impaired hepatic or biliary function, since drug and/or metabolite accumulation may occur.

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Liver Disease.

Phosphodiesterase 5 (PDE-5) inhibitors are cleared predominantly by hepatic metabolism. The pharmacokinetic disposition of these agents has not been assessed in patients with severe hepatic impairment. No dosage modification is recommended for patients with mild to moderate hepatic impairment, however, therapy with these agents should not be administered to patients with severe hepatic impairment. In patients with mild hepatic impairment a lower dose of these agents should be used as initial therapy.

Myeloproliferative Disorders

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Myeloproliferative Disorders.

Prolonged erection greater than 4 hours and priapism (painful erections greater than 6 hours) have been reported during treatment with phosphodiesterase-5 (PDE 5) inhibitors. Priapism may result in penile tissue damage and permanent loss of potency if not treated promptly. These agents should be used cautiously in patients with conditions that may predispose them to priapism such as sickle cell anemia, multiple myeloma, or leukemia, and those with anatomical deformation of the penis (such as angulation, cavernosal fibrosis, or Peyronie's disease). If an erection persists longer than 4 hours, the patient should seek immediate medical assistance.

Neutropenia

Moderate:

doxazosin

Doxazosin has a moderate potential interaction with Neutropenia.

Slight but sometimes clinically significant decreases in white blood cell and neutrophil counts have occurred during treatment with some of the peripheral alpha 1-adrenergic receptor blocking agents (aka alpha 1-blockers), including doxazosin. Reported cases were generally asymptomatic and reversible. Patients with preexisting neutropenia or bone marrow depression may require closer monitoring during therapy with alpha 1-blockers.

Optic Nerve Disorder

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Optic Nerve Disorder.

Sildenafil for the treatment of erectile dysfunction (ED) should be used with caution and only if the benefit outweighs the risk in patients with a history of non-arteritic anterior ischemic optic neuropathy (NAION) or with retinitis pigmentosa. Use of sildenafil for the treatment of pulmonary arterial hypertension is not recommended in patients with retinitis pigmentosa. Advise patients to seek immediate medical attention in the event of a sudden loss of vision in one or both eyes while taking sildenafil; patients taking sildenafil for ED should immediately stop treatment. Most patients who developed NAION during therapy with sildenafil had underlying anatomic or vascular risk factors, including low cup to disc ratio ("crowded disc").

Penis Disorders

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Penis Disorders.

Prolonged erection greater than 4 hours and priapism (painful erections greater than 6 hours) have been reported during treatment with phosphodiesterase-5 (PDE 5) inhibitors. Priapism may result in penile tissue damage and permanent loss of potency if not treated promptly. These agents should be used cautiously in patients with conditions that may predispose them to priapism such as sickle cell anemia, multiple myeloma, or leukemia, and those with anatomical deformation of the penis (such as angulation, cavernosal fibrosis, or Peyronie's disease). If an erection persists longer than 4 hours, the patient should seek immediate medical assistance.

Peptic Ulcer

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Peptic Ulcer.

The safety of sildenafil in patients with bleeding disorders or active peptic ulceration is unknown. In clinical studies, the incidence of bleeding (i.e., epistaxis) was increased in patients with pulmonary arterial hypertension secondary to connective tissue disease and in patients on concomitant therapy with an oral vitamin K antagonist. There have been postmarketing reports of bleeding events in patients treated with sildenafil for erectile dysfunction.

Peyronie Disease

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Peyronie Disease.

Prolonged erection greater than 4 hours and priapism (painful erections greater than 6 hours) have been reported during treatment with phosphodiesterase-5 (PDE 5) inhibitors. Priapism may result in penile tissue damage and permanent loss of potency if not treated promptly. These agents should be used cautiously in patients with conditions that may predispose them to priapism such as sickle cell anemia, multiple myeloma, or leukemia, and those with anatomical deformation of the penis (such as angulation, cavernosal fibrosis, or Peyronie's disease). If an erection persists longer than 4 hours, the patient should seek immediate medical assistance.

Renal Dysfunction

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Renal Dysfunction.

Exposure to sildenafil is increased in patients with renal dysfunction. Lower starting doses of sildenafil for the treatment of erectile dysfunction (ED) are recommended in patients with severe renal impairment (CrCl less than 30 mL/min). When sildenafil is used for the treatment of pulmonary arterial hypertension, no dose adjustment is recommended for any degree of renal impairment.

Retinitis Pigmentosa

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Retinitis Pigmentosa.

Sildenafil for the treatment of erectile dysfunction (ED) should be used with caution and only if the benefit outweighs the risk in patients with a history of non-arteritic anterior ischemic optic neuropathy (NAION) or with retinitis pigmentosa. Use of sildenafil for the treatment of pulmonary arterial hypertension is not recommended in patients with retinitis pigmentosa. Advise patients to seek immediate medical attention in the event of a sudden loss of vision in one or both eyes while taking sildenafil; patients taking sildenafil for ED should immediately stop treatment. Most patients who developed NAION during therapy with sildenafil had underlying anatomic or vascular risk factors, including low cup to disc ratio ("crowded disc").

Seizures

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Seizures.

The use of phosphodiesterase 5 (PDE-5) inhibitors has been associated with seizures. Therapy with these agents should be administered cautiously in patients with preexisting seizure disorders.

Sickle Cell Anemia

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Sickle Cell Anemia.

The safety and efficacy of sildenafil for the treatment of pulmonary hypertension secondary to sickle cell disease has not been established; vaso-occlusive crises requiring hospitalization were more commonly reported in this population.

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Sickle Cell Anemia.

Prolonged erection greater than 4 hours and priapism (painful erections greater than 6 hours) have been reported during treatment with phosphodiesterase-5 (PDE 5) inhibitors. Priapism may result in penile tissue damage and permanent loss of potency if not treated promptly. These agents should be used cautiously in patients with conditions that may predispose them to priapism such as sickle cell anemia, multiple myeloma, or leukemia, and those with anatomical deformation of the penis (such as angulation, cavernosal fibrosis, or Peyronie's disease). If an erection persists longer than 4 hours, the patient should seek immediate medical assistance.

Syncope

Moderate:

doxazosin

Doxazosin has a moderate potential interaction with Syncope.

Peripheral alpha 1- adrenergic receptor blocking agents (aka alpha 1- blockers) cause vasodilation and can produce marked hypotension, especially orthostatic hypotension with syncope or other postural symptoms such as dizziness, lightheadedness, and palpitations. Orthostatic effects are most common during initiation of therapy and often occur within 90 minutes after the first dose. However, they can also occur following a dosage increase or resumption of therapy after an interruption of more than a few days. Agents with alpha 1a specificity, such as tamsulosin, act primarily on the prostate but are not devoid of hypotensive effects. Therapy with peripheral alpha-1 blockers should be administered cautiously in patients with or predisposed to hypotensive or syncopal episodes. Caution is also advised in patients who are dehydrated (e.g., due to severe or prolonged diarrhea or vomiting), since they may be more sensitive to the hypotensive effect of the drugs. Therapy should be initiated with the lowest dosage possible and titrated gradually based on patient response and tolerance in accordance with the individual product package labeling. During initiation or reinstitution of therapy and following an increase in dosage, patients should be advised not to rise abruptly from a sitting or recumbent position and to avoid situations where injury could result if syncope occur. Concomitant use of alcohol, extensive periods of standing, prolonged or intense exercise, and exposure to heat can also precipitate orthostatic hypotension and should be minimized. If dizziness, lightheadedness or palpitations occur, the patient should sit or lie down, and seek medical attention if symptoms are recurrent or bothersome.

Tinnitus

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Tinnitus.

Use of phosphodiesterase-5 (PDE5) inhibitors has been associated with sudden decrease or loss of hearing, which may be accompanied by tinnitus or dizziness. Patients with hearing problems should stop taking these agents and seek prompt medical care.

Visual Defect/Disturbance

Moderate:

Viagra

The sildenafil in Viagra has a moderate potential interaction with Visual Defect/Disturbance.

Sildenafil for the treatment of erectile dysfunction (ED) should be used with caution and only if the benefit outweighs the risk in patients with a history of non-arteritic anterior ischemic optic neuropathy (NAION) or with retinitis pigmentosa. Use of sildenafil for the treatment of pulmonary arterial hypertension is not recommended in patients with retinitis pigmentosa. Advise patients to seek immediate medical attention in the event of a sudden loss of vision in one or both eyes while taking sildenafil; patients taking sildenafil for ED should immediately stop treatment. Most patients who developed NAION during therapy with sildenafil had underlying anatomic or vascular risk factors, including low cup to disc ratio ("crowded disc").

Vomiting

Moderate:

doxazosin

Doxazosin has a moderate potential interaction with Vomiting.

Peripheral alpha 1- adrenergic receptor blocking agents (aka alpha 1- blockers) cause vasodilation and can produce marked hypotension, especially orthostatic hypotension with syncope or other postural symptoms such as dizziness, lightheadedness, and palpitations. Orthostatic effects are most common during initiation of therapy and often occur within 90 minutes after the first dose. However, they can also occur following a dosage increase or resumption of therapy after an interruption of more than a few days. Agents with alpha 1a specificity, such as tamsulosin, act primarily on the prostate but are not devoid of hypotensive effects. Therapy with peripheral alpha-1 blockers should be administered cautiously in patients with or predisposed to hypotensive or syncopal episodes. Caution is also advised in patients who are dehydrated (e.g., due to severe or prolonged diarrhea or vomiting), since they may be more sensitive to the hypotensive effect of the drugs. Therapy should be initiated with the lowest dosage possible and titrated gradually based on patient response and tolerance in accordance with the individual product package labeling. During initiation or reinstitution of therapy and following an increase in dosage, patients should be advised not to rise abruptly from a sitting or recumbent position and to avoid situations where injury could result if syncope occur. Concomitant use of alcohol, extensive periods of standing, prolonged or intense exercise, and exposure to heat can also precipitate orthostatic hypotension and should be minimized. If dizziness, lightheadedness or palpitations occur, the patient should sit or lie down, and seek medical attention if symptoms are recurrent or bothersome.

More resources

doxazosin

A total of 392 drugs are known to interact with doxazosin.

Viagra

A total of 396 drugs are known to interact with Viagra.

Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No interaction information available.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.