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Tenex (guanfacine) Disease Interactions

There are 5 disease interactions with Tenex (guanfacine):


Alpha-2 Agonists (Central) (Includes Tenex) ↔ Bradyarrhythmia

Moderate Potential Hazard, High plausibility

Applies to: Heart Block, Sinus Node Dysfunction

Central alpha-2 adrenoreceptor agonists reduce sympathetic outflow from the central nervous system. Heart rate is decreased, which may lead to or exacerbate sinus bradycardia and atrioventricular block. Therapy with central alpha-2 adrenoreceptor agonists should be administered cautiously in patients with conduction disturbances such as sinus node dysfunction or AV nodal disease.


  1. van Zwieten PA, Thoolen MJ, Timmermans PB "The hypotensive activity and side effects of methyldopa, clonidine, and guanfacine." Hypertension 6 (1984): 28-33
  2. "Product Information. Catapres (clonidine)." Boehringer-Ingelheim, Ridgefield, CT.
  3. Golusinski LL, Blount BW "Clonidine-induced bradycardia." J Fam Pract 41 (1995): 399-401
View all 7 references

Alpha-2 Agonists (Central) (Includes Tenex) ↔ Depression

Moderate Potential Hazard, Moderate plausibility

Applies to: Depression

Central alpha-2 adrenoreceptor agonists may occasionally cause mental depression and should be used cautiously in patients with a history of depression.


  1. Kostis JB, Rosen RC, Holzer BC, et al "CNS side effects of centrally-active antihypertensive agents: a prospective, placebo-controlled study of sleep, mood state, and cognitive and sexual function in hypertensive males." Psychopharmacology (Berl) 102 (1990): 163-70
  2. Prasad A, Shotliff K "Depression and chronic clonidine therapy." Postgrad Med J 69 (1993): 327-8
  3. "Product Information. Catapres (clonidine)." Boehringer-Ingelheim, Ridgefield, CT.
View all 5 references

Alpha-2 Agonists (Central) (Includes Tenex) ↔ Hypotension

Moderate Potential Hazard, High plausibility

Applies to: Hypotension, Cerebrovascular Insufficiency, Ischemic Heart Disease, Peripheral Arterial Disease

Central alpha-2 adrenoreceptor agonists reduce sympathetic outflow from the central nervous system, resulting in decreases in heart rate, peripheral and renovascular resistance, and blood pressure. Therapy with these agents should be administered cautiously in patients with hypotension or conditions that may be exacerbated by decreased blood pressure and perfusion, such as coronary insufficiency, peripheral vascular disease (e.g., Raynaud's syndrome), cerebrovascular disease, or recent myocardial infarction.


  1. "Product Information. Wytensin (guanabenz)." Wyeth-Ayerst Laboratories, Philadelphia, PA.
  2. Greene CS, Gretler DD, Cervenka K, et al "Cerebral blood flow during the acute therapy of severe hypertension with oral clonidine." Am J Emerg Med 8 (1990): 293-6
  3. Fruncillo RJ, Gibbons WJ, Vlasses PH, Ferguson RK "Severe hypotension associated with concurrent clonidine and antipsychotic medication." Am J Psychiatry 142 (1985): 274
View all 12 references

Guanfacine (Includes Tenex) ↔ Adhd

Moderate Potential Hazard, Moderate plausibility

Applies to: Hyperkinetic Syndrome of Childhood

The safety and effectiveness of guanfacine in children under 12 years of age has not been demonstrated and its use in this age group is not recommended. However, there have been some spontaneous postmarketing reports of mania and aggressive behavioral changes in pediatric patients with attention- deficit hyperactivity disorder (ADHD) that received this drug. All patients had medical or family risks of bipolar disorder, and all of them recovered after treatment discontinuation. Hallucinations have also been reported in pediatric patients receiving guanfacine for the treatment of ADHD.


Guanfacine (Includes Tenex) ↔ Renal/Liver Disease

Moderate Potential Hazard, Low plausibility

Applies to: Liver Disease, Renal Dysfunction

Normally, approximately 50% of a guanfacine dose is eliminated unchanged by the kidney and the rest metabolized by the liver. However, neither the parent drug nor its metabolites accumulate significantly during chronic dosing in patients with severe renal impairment due to increased hepatic metabolism of the drug in these patients. Thus, initial dosage adjustments are generally not necessary in renal impairment. Dosage titration, however, should be made cautiously if hepatic function is also compromised. The pharmacokinetics of guanfacine has not been studied in patients with liver disease. The manufacturer recommends caution when the drug is used in such patients.


  1. Kirch W, Kohler H, Braun W "Elimination of guanfacine in patients with normal and impaired renal function." Br J Clin Pharmacol 10 (1980): s33-5
  2. Kiechel JR "Pharmacokinetics and metabolism of guanfacine in man: a review." Br J Clin Pharmacol 10 (1980): s25-32
  3. Kirch W, Kohler H, Braun W, von Gizycki C "The influence of renal function on plasma concentration, urinary excretion and antihypertensive effect of guanfacine." Clin Pharmacokinet 5 (1980): 476-83
View all 6 references

Tenex (guanfacine) drug Interactions

There are 453 drug interactions with Tenex (guanfacine)

Tenex (guanfacine) alcohol/food Interactions

There is 1 alcohol/food interaction with Tenex (guanfacine)

Drug Interaction Classification

The classifications below are a general guideline only. It is difficult to determine the relevance of a particular drug interaction to any individual given the large number of variables.

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.

Do not stop taking any medications without consulting your healthcare provider.

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