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(ta-da-la-fil) ,


(trade name),


(trade name)


Therapeutic: erectile dysfunction agents
Pharmacologic: phosphodiesterase type 5 inhibitors
Pregnancy Category: B


Cialis: Treatment of:
  • Erectile dysfunction (ED),
  • Benign prostatic hyperplasia (BPH),
  • ED and BPH.
Adcirca: Pulmonary arterial hypertension.


Increases cyclic guanosine monophosphate (cGMP) levels by inhibiting phosphodiesterase type 5 (PDE5) an enzyme responsible for the breakdown of cGMP. cGMP produces smooth muscle relaxation of the corpus cavernosum, which in turn promotes increased blood flow and subsequent erection. cGMP also leads to vasodilation of the pulmonary vasculature.

Therapeutic effects

Cialis: Enhanced blood flow to the corpus cavernosum and erection sufficient to allow sexual intercourse.
Improved signs and symptoms of BPH.
Adcirca: Improved exercise tolerance.


Absorption: Well absorbed following oral administration.
Distribution: Extensive tissue distribution; penetrates semen.
Protein Binding: 94%.
Metabolism and Excretion: Mostly metabolized by the liver (mainly CYP3A4 enzyme system); metabolites are excreted in feces (61%) and urine (36%).
Half-life: 17.5 hr.

Time/action profile (vasodilation, improved erectile function)

POrapid0.5–6 hr36


Contraindicated in: Hypersensitivity;Concurrent use of nitrates;Unstable angina, recent history of stroke, life-threatening heart failure within 6 mo, uncontrolled hypertension, arrhythmias, stroke within 6 mo or MI within 90 days;Any other cardiovascular pathology precluding sexual activity;Known hereditary degenerative retinal disorders;Severe hepatic impairment;Severe renal impairment (Adcirca only);Severe renal impairment (CCr <30 mL/min) (Cialis once daily dosing);Congenital or acquired QT interval prolongation or concurrent use of Class IA or III antiarrhythmics;Concurrent use of ketoconazole, itraconazole, or rifampin (Adcirca only);Alpha adrenergic blockers (when tadalafil used for BPH); Pediatric: Women, children or newborns.
Use Cautiously in: Left ventricular outflow obstruction;Penile deformity;Renal impairment;Underlying conditions predisposing to priapism including sickle cell anemia, multiple myeloma, or leukemia;Bleeding disorders or active peptic ulcer disease;Strong inhibitors of the CYP3A4 enzyme system;Alpha adrenergic blockers (patients should be on stable dose of alpha blockers before starting tadalafil for ED);History of sudden severe vision loss or non arteritic ischemic optic neuropathy (NAION); may ↑ risk of recurrence; Geriatric: May experience more side effects.

Adverse Reactions/Side Effects

Central nervous system

  • headache (most frequent)

Ear, Eye, Nose, Throat

  • hearing loss
  • nasal congestion
  • vision loss


  • hypotension


  • dyspepsia


  • priapism


  • flushing (most frequent)


  • back pain
  • limb pain
  • myalgia


Drug-Drug interaction

Concurrent use of nitrates may cause serious, life threatening hypotension and is contraindicated.↑ risk of hypotension with alpha adrenergic blockers and acute ingestion of alcohol ; discontinue alpha-adrenergic blocker therapy ≥1 day before starting Cialis for BPH.Strong inhibitors of CYP3A4 including ritonavir, ketoconazole, itraconazole ↑ effects and the risk of adverse reactions (dose adjustments recommended; ketoconazole and itraconazole contraindicated with Adcirca). Similar effects may be expected of other inhibitors of CY3A4.CYP3A4 inducers may ↓ effects (rifampin contraindicated with Adcirca).


Cialis (for ED)
Oral (Adults) 10 mg prior to sexual activity (range 5–20 mg; not to exceed one dose/24 hr) or 2.5 mg once daily (max: 5 mg/day); Concurrent use of CYP3A4 inhibitors including itraconazole, ketoconazole and ritonavir—single dose should not exceed 10 mg in any 72 hour period; for once daily dose regimen, should not exceed 2.5 mg/day.

Renal Impairment

Oral (Adults) CCr 30–50 mL/min (as needed dosing)—Initial dose should not exceed 5 mg/day; maximum dose should not exceed 10 mg in 48 hr; CCr <30 mL/min (as needed dosing)—Maximum dose should not exceed 5 mg in 72 hr; CCr <30 mL/min (once daily dosing)—Not recommended for use.

Hepatic Impairment

Oral (Adults) Mild or moderate hepatic impairment (Child–Pugh class A or B)—Daily dose should not exceed 10 mg (once daily dose regimen not recommended) Severe hepatic impairment (Child–Pugh class C)—Not recommended for use.
Cialis (for BPH or ED/BPH)
Oral (Adults) 5 mg once daily; Concurrent use of CYP3A4 inhibitors including itraconazole, ketoconazole and ritonavir—Should not exceed 2.5 mg/day.

Renal Impairment

Oral (Adults) CCr 30–50 mL/min—Initial dose should not exceed 2.5 mg/day; maximum dose should not exceed 5 mg/day; CCr <30 mL/min—Not recommended for use.

Hepatic Impairment

Oral (Adults) Not recommended for use.
Adcirca (for pulmonary arterial hypertension)
Oral (Adults) 40 mg once daily; If receiving ritonavir for ≥1 wk—start 20 mg once daily; may then ↑ to 40 mg once daily based on tolerability; If initiating ritonavir while on Adcirca—stop Adcirca ≥24 hr before starting ritonavir; may reinitiate Adcirca at 20 mg once daily after ≥1 wk of therapy with ritonavir; may then ↑ to 40 mg once daily based on tolerability.

Renal Impairment

(Adults) CCr 31–80 mL/min—Start 20 mg once daily; may then ↑ to 40 mg once daily based on tolerability.

Hepatic Impairment

Oral (Adults) Mild or moderate hepatic impairment (Child–Pugh class A or B)—Start with 20 mg once daily.


Tablets (Cialis): 2.5 mg, 5 mg, 10 mg, 20 mg
Tablets (Adcirca): 20 mg

Nursing implications

Nursing assessment

  • Cialis: for ED : Determine ED before administration. Tadalafil has no effect in the absence of sexual stimulation.
  • Cialis for BPH: Assess for symptoms of prostatic hyperplasia (urinary hesitancy, feeling of incomplete bladder emptying, interruption of urinary stream, impairment of size and force of urinary stream, terminal urinary dribbling, straining to start flow, dysuria, urgency) before and periodically during therapy.
  • Digital rectal examinations should be performed before and periodically during therapy for BPH.
  • Adcirca: Monitor hemodynamic parameters and exercise tolerance prior to and periodically during therapy.

Potential Nursing Diagnoses

Sexual dysfunction (Indications)
Impaired urinary elimination (Indications)
Risk for activity intolerance (Indications)


  • Oral: Administer dose as needed for ED at least 30 min prior to sexual activity; effectiveness may continue for 36 hr.
    • Administer dose for pulmonary hypertension, BPH, ED/BPH, or daily for ED once daily at the same time each day.
    • May be administered without regard to food. Swallow tablets whole; do not crush, break, or chew.

Patient/Family Teaching

  • Instruct patient to take tadalafil as needed for ED at least 30 min before sexual activity and not more than once per day. Inform patient that sexual stimulation is required for an erection to occur after taking tadalafil.
  • Advise patient that tadalafil is not indicated for use in women.
  • Caution patient not to take tadalafil concurrently with alpha adrenergic blockers (unless on a stable dose) or nitrates. If chest pain occurs after taking tadalafil, instruct patient to seek immediate medical attention.
  • Advise patient to avoid excess alcohol intake (≥5 units) in combination with tadalafil; may increase risk of orthostatic hypotension, increased heart rate, decreased standing BP, dizziness, headache.
  • Instruct patient to notify health care professional promptly if erection lasts longer than 4 hr, if they are not satisfied with their sexual performance or develop unwanted side effects or if they experience sudden or decreased vision loss in one or both eyes or loss or decrease in hearing, ringing in the ears, or dizziness.
  • Advise patient to notify health care professional of all Rx or OTC medications, vitamins, or herbal products being taken and to consult with health care professional before taking other medications that may interact with tadalafil.
  • Inform patient that tadalafil offers no protection against sexually transmitted diseases. Counsel patient that protection against sexually transmitted diseases and HIV infection should be considered.

Evaluation/Desired Outcomes

  • Male erection sufficient to allow intercourse.
  • Decrease in urinary symptoms of benign prostatic hyperplasia.
  • Increased exercise tolerance.


A drug that inhibits phosphodiesterase, C22H19N3O4, used to treat erectile dysfunction by increasing the level of cyclic GMP, which increases blood flow to the erectile tissues.


an impotence agent.
indication This drug is used in the treatment of erectile dysfunction.
contraindications Known hypersensitivity to this drug prohibits its use. Patients who are taking organic nitrates either regularly or intermittently and patients taking any alpha-adrenergic antagonist other than tamsulosin (0.4 mg once daily) should not take this drug.
adverse effects Adverse effects of this drug include back pain or myalgia, blurred vision, changes in color vision, and pruritus. Life-threatening side effects include myocardial infarction, cardiovascular collapse, and sudden death. Common side effects include headache, flushing, dizziness, dyspepsia, nasal congestion, urinary tract infection, and diarrhea.


An inhibitor of the enzyme phosphodiesterase-5 which limits penile erection (see SILDENAFIL CITRATE for fuller details), used in the treatment of impotence. The drug takes effect within half an hour, reaches maximum blood concentration in two hours and remains effective for up to 36 hours. It has been available in Britain since February 2003. A brand name is Cialis.