- High Blood Pressure Slideshow Pictures
- Take the Salt Quiz!
- Lowering Blood Pressure Exercise Tips Pictures
Does Tenex (guanfacine) cause side effects?
Common side effects of Tenex include
Serious side effects of Tenex include
- hair loss,
- memory impairment,
- heart failure,
- skin problems,
- difficulty swallowing,
- hypersensitivity or allergic reactions,
- heart attack,
- rebound hypertension,
- kidney failure,
- rapid heartbeat, and
- visual disturbance.
Drug interactions of Tenex include rifampin and St. John's wort, which may reduce blood levels of Tenex by increasing its metabolism (breakdown) in the intestine; doses of Tenex may need to be increased when combined with drugs that reduce its blood levels.
Other drugs that also may reduce blood levels of Tenex include
- bosentan, and
Ketoconazole, itraconazole, and simeprevir may increase blood levels of Tenex by decreasing its metabolism in the intestine; the dose of Tenex may need to be decreased when combined with drugs that increase its blood levels.
What are the important side effects of Tenex (guanfacine)?
Use Intuniv with caution in patients at risk for hypotension, bradycardia, heart block, or syncope (e.g., those taking antihypertensives). Measure heart rate and blood pressure prior to initiation of therapy, following dose increases, and periodically while on therapy. Advise patients to avoid becoming dehydrated or overheated.
Sedation and somnolence occur commonly with Intuniv
Consider the potential for additive sedative effects with CNS depressant drugs. Caution patients against operating heavy equipment or driving until they know how they respond to Intuniv.
Common side effects
The most common side effects associated with guanfacine treatment are
Other important side effects that are rare, but serious, are:
Tenex (guanfacine) side effects list for healthcare professionals
Adverse reactions noted with Tenex (guanfacine hydrochloride) are similar to those of other drugs of the central α2-adrenoreceptor agonist class:
While the reactions are common, most are mild and tend to disappear on continued dosing.
Skin rash with exfoliation has been reported in a few cases; although clear cause and effect relationships to Tenex could not be established, should a rash occur, Tenex should be discontinued and the patient monitored appropriately.
In the dose-response monotherapy study described in the prescribing information, the frequency of the most commonly observed adverse reactions showed a dose relationship from 0.5 to 3 mg as follows:
The percent of patients who dropped out because of adverse reactions are shown below for each dosage group.
|Placebo||0.5 mg||1 mg||2 mg||3 mg|
The most common reasons for dropouts among patients who received guanfacine were
In the 12-week, placebo-controlled, dose-response study of guanfacine administered with 25 mg chlorthalidone at bedtime, the frequency of the most commonly observed adverse reactions showed a clear dose relationship from 0.5 to 3 mg as follows:
|Dry Mouth||5 (7%)||4 (5%)||6 (8%)||8 (11%)||20 (28%)|
|Somnolence||1 (1%)||3 (4%)||0 (0%)||1 (1%)||10 (14%)|
|Asthenia||0 (0%)||2 (3%)||0 (0%)||2 (2%)||7 (10%)|
|Dizziness||2 (2%)||1 (1%)||3 (4%)||6 (8%)||3 (4%)|
|Headache||3 (4%)||4 (3%)||3 (4%)||1 (1%)||2 (2%)|
|Impotence||1 (1%)||1 (0%)||0 (0%)||1 (1%)||3 (4%)|
|Constipation||0 (0%)||0 (0%)||0 (0%)||1 (1%)||1 (1%)|
|Fatigue||3 (3%)||2 (3%)||2 (3%)||5 (6%)||3 (4%)|
There were 41 premature terminations because of adverse reactions in this study. The percent of patients who dropped out and the dose at which the dropout occurred were as follows:
|Dose||Placebo||0.5 mg||1 mg||2 mg||3 mg|
Reasons for dropouts among patients who received guanfacine were:
- dry mouth,
- urinary incontinence,
- paresthesia, and
In a second 12-week placebo-controlled combination therapy study in which the dose could be adjusted upward to 3 mg per day in 1-mg increments at 3-week intervals, i.e., a setting more similar to ordinary clinical use, the most commonly recorded reactions were:
- dry mouth, 47%;
- constipation, 16%;
- fatigue, 12%;
- somnolence, 10%;
- asthenia, 6%;
- dizziness, 6%;
- headache, 4%; and
- insomnia, 4%.
Reasons for dropouts among patients who received guanfacine were:
In the clonidine/guanfacine comparison described in the prescribing information, the most common adverse reactions noted were as follows:
Adverse reactions occurring in 3% or less of patients in the three controlled trials of Tenex (guanfacine hydrochloride) with a diuretic were:
- Cardiovascular- bradycardia, palpitations, substernal pain
- Gastrointestinal- abdominal pain, diarrhea, dyspepsia, dysphagia, nausea
- CNS- amnesia, confusion, depression, insomnia, libido decrease
- ENT disorders- rhinitis, taste perversion, tinnitus
- Eye disorders- conjunctivitis, iritis, vision disturbance
- Musculoskeletal- leg cramps, hypokinesia
- Respiratory- dyspnea
- Dermatologic- dermatitis, pruritus, purpura, sweating
- Urogenital- testicular disorder, urinary incontinence
- Other- malaise, paresthesia, paresis
Adverse reaction reports tend to decrease over time. In an open-label trial of one year's duration, 580 hypertensive subjects were given guanfacine, titrated to achieve goal blood pressure, alone (51%), with diuretic (38%), with beta blocker (3%), with diuretic plus beta blocker (6%), or with diuretic plus vasodilator (2%). The mean daily dose of guanfacine reached was 4.7 mg.
|Adverse Reaction||Incidence of adverse reactions at any time during the study
n = 580
|Incidence of adverse reactions at end of one year
n = 580
There were 52 (8.9%) dropouts due to adverse effects in this 1-year trial. The causes were:
- dry mouth (n = 20),
- weakness (n = 12),
- constipation (n = 7),
- somnolence (n = 3),
- nausea (n = 3),
- orthostatic hypotension (n = 2),
- insomnia (n = 1),
- rash (n = 1),
- nightmares (n = 1),
- headache (n = 1), and
- depression (n = 1).
An open-label postmarketing study involving 21,718 patients was conducted to assess the safety of Tenex (guanfacine hydrochloride) 1 mg/day given at bedtime for 28 days. Tenex was administered with or without other antihypertensive agents.
Adverse events reported in the postmarketing study at an incidence greater than 1% included
The most commonly reported adverse events in this study were the same as those observed in controlled clinical trials.
Less frequent, possibly Tenex-related events observed in the postmarketing study and/or reported spontaneously include:
- Body As A Whole: asthenia, chest pain, edema, malaise, tremor
- Cardiovascular: bradycardia, palpitations, syncope, tachycardia
- Central Nervous System: paresthesias, vertigo
- Eye Disorders: blurred vision
- Gastrointestinal System: abdominal pain, constipation, diarrhea, dyspepsia
- Liver And Billiary System: abnormal liver function tests
- Musculoskeletal System: arthralgia, leg cramps, leg pain, myalgia
- Psychiatric: agitation, anxiety, confusion, depression, insomnia, nervousness
- Rreproductive System: Male impotence
- Respiratory System: dyspnea
- Skin And Appendages: alopecia, dermatitis, exfoliative dermatitis, pruritus, rash
- Special Senses: alterations in taste
- Urinary System: nocturia, urinary frequency
Rare, serious disorders with no definitive cause and effect relationship to Tenex have been reported spontaneously and/or in the postmarketing study. These events include
Does Tenex (guanfacine) cause addiction or withdrawal symptoms?
Drug Abuse And Dependence
No reported abuse or dependence has been associated with the administration of Tenex (guanfacine hdyrochloride).
What drugs interact with Tenex (guanfacine)?
The potential for increased sedation when Tenex is given with other CNS-depressant drugs should be appreciated.
The administration of guanfacine concomitantly with a known microsomal enzyme inducer (phenobarbital or phenytoin) to two patients with renal impairment reportedly resulted in significant reductions in elimination half-life and plasma concentration. In such cases, therefore, more frequent dosing may be required to achieve or maintain the desired hypotensive response. Further, if guanfacine is to be discontinued in such patients, careful tapering of the dosage may be necessary in order to avoid rebound phenomena.
Ten patients who were stabilized on oral anticoagulants were given guanfacine, 1 - 2 mg/day, for 4 weeks. No changes were observed in the degree of anticoagulation.
In several well-controlled studies, guanfacine was administered together with diuretics with no drug interactions reported. In the long-term safety studies, Tenex was given concomitantly with many drugs without evidence of any interactions.
The principal drugs given (number of patients in parentheses) were:
- cardiac glycosides (115),
- sedatives and hypnotics (103),
- coronary vasodilators (52),
- oral hypoglycemics (45),
- cough and cold preparations (45),
- NSAIDs (38),
- antihyperlipidemics (29),
- antigout drugs (24),
- oral contraceptives (18),
- bronchodilators (13),
- insulin (10), and
- beta blockers (10).
Drug/Laboratory Test Interactions
No laboratory test abnormalities related to the use of Tenex (guanfacine hydrochloride) have been identified.
Tenex (guanfacine) is a centrally-acting alpha 2A adrenergic receptor agonist used alone or in combination with other medications to treat hypertension (high blood pressure). Common side effects of Tenex include tiredness, sleepiness, trouble sleeping, nausea, low blood pressure, stomach pain, and dizziness. There are no adequate and well-controlled studies of Tenex in pregnant women. It is unknown if Tenex is excreted in breast milk.
Multimedia: Slideshows, Images & Quizzes
High Blood Pressure (Hypertension) Quiz: Symptoms, Signs & Causes
Take this quiz and test your IQ of high blood pressure (hypertension), the cardiovascular disease that causes most strokes and...
Picture of Hypertension
High blood pressure, defined as a repeatedly elevated blood pressure exceeding 140 over 90 mmHg -- a systolic pressure above 140...
High Blood Pressure (Hypertension): Symptoms, Causes, Treatments
What causes high blood pressure (hypertension)? Know the warning signs and symptoms of high blood pressure. Read about high blood...
Hypertension: What High Blood Pressure Can Do to Your Body
High blood pressure puts you at risk for a number of other conditions. Here's what to look out for.
Hypertension: 15 Surprising Things That Raise Your Blood Pressure
Salt, worry, and anger aren't the only things that can raise your blood pressure. Risk factors like loneliness and birth control...
Related Disease Conditions
Hypertension-Related Kidney Disease
Second Source WebMD Medical Reference
High Blood Pressure (Hypertension)
High blood pressure (hypertension) is a disease in which pressure within the arteries of the body is elevated. About 75 million people in the US have hypertension (1 in 3 adults), and only half of them are able to manage it. Many people do not know that they have high blood pressure because it often has no has no warning signs or symptoms. Systolic and diastolic are the two readings in which blood pressure is measured. The American College of Cardiology released new guidelines for high blood pressure in 2017. The guidelines now state that blood normal blood pressure is 120/80 mmHg. If either one of those numbers is higher, you have high blood pressure. The American Academy of Cardiology defines high blood pressure slightly differently. The AAC considers 130/80 mm Hg. or greater (either number) stage 1 hypertension. Stage 2 hypertension is considered 140/90 mm Hg. or greater. If you have high blood pressure you are at risk of developing life threatening diseases like stroke and heart attack.REFERENCE: CDC. High Blood Pressure. Updated: Nov 13, 2017.
Pulmonary hypertension is elevated pressure in the pulmonary arteries that carry blood from the lungs to the heart. The most common symptoms are fatigue and difficulty breathing. If the condition goes undiagnosed, more severe symptoms may occur. As pulmonary hypertension worsens, some people with the condition have difficulty performing any activities that require physical exertion. While there is no cure for pulmonary hypertension, it can be managed and treated with medications and supplemental oxygen to increase blood oxygen levels.
Pseudotumor Cerebri (Idiopathic Intracranial Hypertension)
Pseudotumor Cerebri (intracranial hypertension) is a condition where there is an increase in pressure of fluid surrounding the brain and spinal cord (cerebrospinal fluid or CSF) mimicing a brain tumor. The cause is unknown. The most common symptom is headache but also include eye-pain, vision loss and double vision. Pseudotumor cerebri is diagnosed with MRI or CAT scans and treated by discontinuing offending medications (if applicable), weight loss and diuretic medications. The condition can also be helped by repeated drainage of spinal fluid using the lumbar puncture.
Preeclampsia (Pregnancy Induced Hypertension)
Preeclampsia is related to increased blood pressure and protein in the mother's urine. Preeclampsia typically begins after the 20th week of pregnancy. When preeclampsia causes seizures, it is termed "eclampsia" and is the second leading cause of maternal death of in the US. Preeclampsia is the leading cause of fetal complications. Risk factors for preeclampsia include high blood pressure, obesity, multiple births, and women with preexisting medical conditions such as diabetes, kidney disease, rheumatoid arthritis, lupus, or scleroderma. Pregnancy planning and lifestyle changes may reduce the risk of preeclampsia during pregnancy.
Portal hypertension is most commonly caused by cirrhosis, a disease that results from scarring of the liver. Other causes of portal hypertension include blood clots in the portal vein, blockages of the veins that carry the blood from the liver to the heart, and a parasitic infection called schistosomiasis. Symptoms of portal hypertension include varices (enlarged veins), vomiting blood, blood in the stool, black and tarry stool, ascites (abnormal fluid collection within the peritoneum, the sac that contains the intestines within the abdominal cavity), confusion and lethargy, splenomegaly or enlargement of the spleen, and decreased white blood cell counts.
Hypertensive Kidney Disease
High blood pressure can damage the kidneys and is one of the leading causes of kidney failure (end-stage renal kidney disease). Kidney damage, like hypertension, can be unnoticeable and detected only through medical tests. If you have kidney disease, you should control your blood pressure. Other treatment options include prescription medications.
High Blood Pressure Treatment (Natural Home Remedies, Diet, Medications)
High blood pressure (hypertension) means high pressure (tension) in the arteries. Treatment for high blood pressure include lifestyle modifications (alcohol, smoking, coffee, salt, diet, exercise), drugs and medications such as ACE inhibitors, angiotensin receptor blockers, beta blockers, diuretics, calcium channel blockers (CCBs), alpha blockers, clonidine, minoxidil, and Exforge.
What Is High Blood Pressure (Hypertension)?
High blood pressure or hypertension is when the blood pressure readings consistently range from 140 or higher for systolic or 90 or higher for diastolic. Blood pressure readings above 180/120 mmHg are dangerously high and require immediate medical attention.
High Blood Pressure Symptoms
Most people with high blood pressure have no signs or symptoms, even if blood pressure readings reach dangerously high levels. In some patients, symptoms may include fatigue, headaches, dizziness, confusion, sweating, chest pain and vision problems.
Treatment & Diagnosis
- High Blood Pressure FAQs
- Hypertension In The Elderly - Deserves More Attention
- Salt, DASH, High Blood Pressure
- High Blood Pressure and Exercise
- High Blood Pressure: Questions To Ask Your Doctor
- Inherited High Blood Pressure in a Teenager
- What Does Hypertension Urgency Mean?
- Does Menopause Cause High Blood Pressure?
- Can I Lift Weights with High Blood Pressure?
- High Blood Pressure Symptoms
- Pain Relievers and High Blood Pressure
- Heart Healthy Diet: Hypertension & Heart Disease
- High Blood Pressure: Improve Your Lifestyle
Medications & Supplements
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
Professional side effects, drug interactions, and addiction sections courtesy of the U.S. Food and Drug Administration.