Many people know Cialis as an erection pill, so it can be confusing to get it from a urologist for trouble urinating, or to find a box of “tadalafil” with a different brand name in a relative’s cabinet. The answer sits in the labels: one molecule, three FDA-approved purposes across two families of products.
The Cialis prescribing information on DailyMed (the version posted in June 2026) says Cialis is a phosphodiesterase 5 (PDE5) inhibitor indicated for the treatment of:
- erectile dysfunction (ED);
- the signs and symptoms of benign prostatic hyperplasia (BPH), the noncancerous prostate enlargement that can cause urinary symptoms;
- ED and the signs and symptoms of BPH together (ED/BPH).
A fourth use, pulmonary arterial hypertension (PAH), is not on the Cialis label at all. It belongs to tadalafil sold as Adcirca and Alyq, whose labels cover PAH (WHO Group 1) “to improve exercise ability.”
The indications at a glance
| Condition | Brand on the label | What the label says | Who to ask about it |
|---|---|---|---|
| Erectile dysfunction | Cialis (and generic tadalafil for ED) | Indicated for ED; available for use as needed or once daily. Sexual stimulation is required for an effect. | The clinician who prescribes your ED treatment |
| BPH urinary symptoms | Cialis | Indicated for the signs and symptoms of BPH, studied with the International Prostate Symptom Score (IPSS) | The clinician treating your urinary symptoms, often a urologist |
| ED plus BPH | Cialis | Indicated for both at once | Same prescriber, ideally aware of both problems |
| BPH with finasteride | Cialis | Limitation of use: when started together with finasteride, use is recommended for up to 26 weeks | The prescriber who chose the combination |
| Pulmonary arterial hypertension | Adcirca, Alyq | Indicated for PAH (WHO Group 1) to improve exercise ability | The clinician managing the PAH |
MedlinePlus puts the same split in plain language: tadalafil (Cialis) treats ED and BPH symptoms such as difficulty urinating, painful urination and urinary frequency and urgency in adult men, while tadalafil (Adcirca) improves the ability to exercise in people with PAH.
How one drug ends up with three jobs
PDE5 is an enzyme that breaks down cGMP, a chemical messenger that relaxes smooth muscle. Block the enzyme and cGMP builds up. The Cialis label notes that this effect is seen in the penis and the pulmonary arteries, and also “in the smooth muscle of the prostate, the bladder and their vascular supply.” MedlinePlus describes the PAH effect as relaxing the blood vessels in the lungs so blood flows more easily.
So the brand on the box tells you which use the product was studied and approved for, and how it is packaged and dosed for that use. The Adcirca label, for example, describes a once-daily regimen at a higher total daily amount than the Cialis once-daily regimens for ED or BPH. That is a label fact, not a reason to compare tablets at home: the strengths and schedules are set for different diseases.
Reading the name on the bottle
Brand names make the split easy to see, but generic packaging can blur it. The Alyq label describes the product as “tadalafil tablets, USP,” and its indication is PAH, not ED. A pharmacy label that just says “tadalafil” therefore does not tell you, on its own, which use the prescription is for. The prescription, the directions on the label and the prescriber’s notes do.
MedlinePlus sums up the practical rule: tadalafil is available under the brand names Adcirca and Cialis, and “you should only be treated with one of these products at a time.” If two prescribers are involved, for example a urologist and a lung or heart specialist, make sure each one has your full medicine list, and keep using a single pharmacy where you can, so duplicate tadalafil prescriptions are easier to spot.
Why the finasteride combination has a time note
The Cialis label contains an unusual line called a limitation of use. If Cialis is started together with finasteride, a different medicine used for an enlarged prostate, the label recommends that use for up to 26 weeks. The reason comes from a 26-week trial of 696 men with an enlarged prostate who started finasteride with either Cialis or placebo.
The Cialis group improved more on the IPSS from the first visit at week 4, and the score stayed lower through week 26. But the extra benefit over finasteride alone shrank, from 1.7 points at week 4 to 1.0 point at week 26, and the label states that the incremental benefit of Cialis beyond 26 weeks is unknown. In other words, the added effect was largest early in the trial, and the data stop at 26 weeks. Whether to continue after that point is a conversation to have with the prescriber, not a reason to stop on your own.
Three situations that bring people here
“My urologist prescribed it for urination, not sex”
That is a labeled use. In the BPH trials described on the Cialis label, the main outcome was the IPSS, a questionnaire scoring frequency, urgency, waking at night to urinate, incomplete emptying, stop-start flow, weak stream and straining, on a scale from 0 to 35. In two placebo-controlled 12-week trials, once-daily Cialis produced a statistically significant improvement in the total score compared with placebo; in one of them the decrease was seen from the first scheduled visit at 4 weeks.
The label adds a practical point many people miss: Cialis is not recommended in combination with alpha-blockers (a common family of prostate medicines) for the treatment of BPH. If you already take an alpha-blocker, or had one before, mention it. If you use it for both ED and BPH, the combined ED/BPH indication covers that. Our article on daily versus as-needed tadalafil explains why some prescriptions are written for every day.
“I found Adcirca on a relative’s shelf, and it says tadalafil”
It is the same active ingredient, prescribed for a different and serious condition. The tablets, strength and schedule are set for PAH, and the medicine is part of a treatment plan for the person it was prescribed for. Using it for ED would mean taking an unknown amount outside any medical review, with the same nitrate and blood-pressure risks that apply to Cialis. If you are worried about a family member’s medicines, the safest move is to leave them in place and ask their pharmacist or prescriber.
“I take tadalafil for PAH and want something for erections”
This is the case where overlap is most likely, and both labels address it directly. The Cialis label tells prescribers to inform patients “not to take CIALIS with other PDE5 inhibitors, including ADCIRCA.” The Adcirca label notes that tadalafil is also marketed for ED and says patients taking Adcirca should be told not to take other PDE5 inhibitors. MedlinePlus says you should only be treated with one of these products at a time. Bring the question to the PAH team first.
The labels give several reasons. Taking two tadalafil products, or tadalafil plus sildenafil, vardenafil or avanafil, stacks the same drug effect, and the safety of these combinations has not been studied. Both Cialis and Adcirca are contraindicated with any organic nitrate and with guanylate cyclase stimulators such as riociguat, and both list a serious allergy to either brand as a contraindication. Our guide to ED medicines, nitrates and blood pressure explains the nitrate interaction.
What Cialis does not treat
The label and its patient information are specific about limits. The patient leaflet states that Cialis does not:
- cure ED;
- increase a man’s sexual desire;
- protect against sexually transmitted infections, including HIV;
- serve as a male form of birth control.
It also states that Cialis “is not for women or children,” and the pregnancy and lactation sections say Cialis is not indicated for use in females. Tadalafil for PAH is a separate matter: the Adcirca label does not carry that line and has its own pregnancy section.
Premature ejaculation is not on the Cialis indication list either. We cover what the evidence shows in does Viagra or Cialis make you last longer. And Cialis is not a hormone: its label describes it as an enzyme inhibitor acting on blood flow and smooth muscle, not as testosterone or a testosterone booster.
Side effects follow the drug, not the brand
Because the molecule is the same, the warnings travel with it: the risk of low blood pressure with nitrates, sudden vision loss that could signal optic nerve damage, sudden decrease or loss of hearing, and erections lasting longer than 4 hours. Back pain and muscle aches are among the effects the Cialis label lists. For a closer look at what is common and what is urgent, see tadalafil side effects and red flags.
Urinary symptoms in men can have several causes. A Cialis prescription for BPH usually follows an assessment by the prescriber, and the label’s BPH studies enrolled men whose symptoms were scored and followed over time. If symptoms change or worsen, that is a reason for a new visit rather than a change you make on your own.
Questions to ask your prescriber
- Which of the labeled uses is this prescription for: ED, BPH symptoms, or both?
- Is it written for as-needed use or once daily, and why that schedule for my condition?
- I take an alpha-blocker, a nitrate, riociguat or a blood pressure medicine. Does that change anything?
- Someone in my household takes Adcirca or Alyq. How do we keep the medicines apart?
- If this is with finasteride for BPH, how long do you plan to continue tadalafil, given the label’s 26-week note?
- Which symptoms should make me call you, and which mean emergency care?
Sources
- DailyMed: Cialis (tadalafil) prescribing information and patient information
- DailyMed: Adcirca (tadalafil) prescribing information
- DailyMed: Alyq (tadalafil tablets) prescribing information
- MedlinePlus: Tadalafil
Evidence checked November 2, 2026. Label wording quoted from the current DailyMed versions; labels are revised over time. This page does not replace advice from the clinician who prescribed your medicine.