Guanethidine Interactions

See WARNINGS section for interaction details with amitriptyline hydrochloride.

Source: NLP:amitriptyline hydrochloride

Catecholamine-depleting drug that may produce excessive reduction of sympathetic activity when combined with bisoprolol fumarate; close monitoring required.

Source: NLP:bisoprolol fumarate

Catecholamine-depleting drug that with bisoprolol's beta-adrenergic blocking action may produce excessive reduction of sympathetic activity. Close monitoring required.

Source: NLP:bisoprolol fumarate and hydrochlorothiazide

Minoxidil may interact with guanethidine, requiring careful monitoring. See WARNINGS section for detailed interaction information.

Source: NLP:minoxidil

Catecholamine-depleting drug; concomitant use may produce excessive reduction of sympathetic activity. Closely monitor patients.

Source: NLP:nebivolol

Catecholamine-depleting drug may produce excessive reduction of sympathetic activity when combined with nebivolol's β-blocking action.

Source: NLP:nebivolol hydrochloride

Concurrent use with sodium phosphate may result in hypernatremia.

Source: NLP:dibasic sodium phosphate, monobasic potassium phosphate and monobasic sodium phosphate

Catecholamine-depleting agent; may produce excessive reduction of resting sympathetic nervous tone, causing hypotension and/or marked bradycardia.

Source: NLP:sotalol hydrochloride

Gastrointestinal acidifying agent that lowers amphetamine absorption and blood levels.

Source: NLP:amphetamine sulfate

Tricyclic antidepressants may block the pharmacologic effects of guanethidine.

Source: NLP:clomipramine hydrochloride

Tricyclic antidepressants including clomipramine may block the pharmacologic effects of guanethidine.

Source: NLP:clomipramine hydrochloride capsules

Tricyclic antidepressants may block the antihypertensive action of guanethidine.

Source: NLP:cyclobenzaprine

Tricyclic antidepressants may block the antihypertensive action of guanethidine.

Source: NLP:cyclobenzaprine hydrochloride

Gastrointestinal acidifying agent lowers amphetamine absorption and blood levels, reducing efficacy.

Source: NLP:dextroamphetamine

Acidifying agent that lowers blood levels and efficacy of amphetamines. Dose adjustment may be needed based on clinical response.

Source: NLP:dextroamphetamine saccharate, amphetamine aspartate, dextroamphetamine sulfate and amphetamine sulfate

Gastrointestinal acidifying agent that lowers amphetamine absorption and blood levels.

Source: NLP:dextroamphetamine sulfate

Pressor effects are additive; diethylpropion may interfere with antihypertensive efficacy.

Source: NLP:diethylpropion hydrochloride

Ephedrine may inhibit neuron blockage produced by guanethidine, resulting in loss of antihypertensive effectiveness. Monitor blood pressure and adjust dosage.

Source: NLP:ephedrine sulfate

Epinephrine may antagonize neuronal blockade produced by guanethidine, decreasing antihypertensive effect.

Source: NLP:epinephrine

May increase glucose-lowering effect of glimepiride, increasing susceptibility to and/or intensity of hypoglycemia.

Source: NLP:glimepiride

May mask signs of hypoglycemia in patients taking glipizide.

Source: NLP:glipizide

May blunt signs and symptoms of hypoglycemia. Increased frequency of glucose monitoring required.

Source: NLP:insulin aspart

May blunt signs and symptoms of hypoglycemia. Increased glucose monitoring may be required.

Source: NLP:insulin aspart-szjj

May blunt signs and symptoms of hypoglycemia. Increased glucose monitoring may be required.

Source: NLP:insulin degludec

May blunt signs and symptoms of hypoglycemia; increased glucose monitoring may be required.

Source: NLP:insulin glargine

May blunt signs and symptoms of hypoglycemia. Increased frequency of glucose monitoring may be required.

Source: NLP:insulin glulisine

May blunt signs and symptoms of hypoglycemia; increased glucose monitoring required.

Source: NLP:insulin human

May blunt signs and symptoms of hypoglycemia; increased glucose monitoring required.

Source: NLP:insulin lispro

May blunt signs and symptoms of hypoglycemia. Increased frequency of glucose monitoring may be required.

Source: NLP:insulin lispro-aabc

Antihypertensive effect of alpha-adrenergic blocker may be potentiated by metoprolol.

Source: NLP:metoprolol

Beta-blocker may potentiate antihypertensive effect of alpha-adrenergic agent.

Source: NLP:metoprolol tartrate

May increase blood-glucose-lowering effect and blunt hypoglycemia symptoms; dose adjustment and monitoring required.

Source: NLP:nateglinide

Concurrent use with sodium phosphate may result in hypernatremia.

Source: NLP:potassium phosphate, monobasic and sodium phosphate, monobasic, anhydrous

Used together without unexpected adverse interactions in clinical practice.

Source: NLP:pindolol