October 12, 2026 · By the ShopMedRx team
Tadalafil Side Effects: Common, Serious and Long Term
Tadalafil side effects explained: what is common, what is rare but serious, what we know about long-term use, and what to ask a licensed clinician.
By the ShopMedRx team. This article is for general education and is not medical advice.
The most common tadalafil side effects are headache, indigestion, back pain, muscle aches, flushing and a stuffy nose. [1] Serious side effects are rare, but they include an erection that lasts more than 4 hours, sudden vision or hearing loss, and a dangerous drop in blood pressure when tadalafil is mixed with nitrate medicines. [6]
This guide goes through each of these in plain language. It covers how often they showed up in clinical trials, when they tend to start, what we know about long-term use, and what to ask a licensed clinician. Tadalafil is a prescription-only medicine, and a clinician decides whether it is appropriate for you.
What is tadalafil and what does it do?
Tadalafil is a prescription tablet taken by mouth by adults. The FDA label for tadalafil tablets describes use for erectile dysfunction (ED), for benign prostatic hyperplasia (BPH), and for ED and BPH together, either as needed or as a once-daily dose. [3] It belongs to a group of medicines called phosphodiesterase (PDE) inhibitors, and it has close relatives in the same class. [5]
If you are asking "what does tadalafil do" for ED, the short answer is that it is used to help a man get and keep an erection when he is sexually stimulated. It does not cause an erection on its own. For a full overview of how it compares with sildenafil, see our article on sildenafil vs tadalafil. This post stays focused on side effects.
Common tadalafil side effects
The label lists the most common adverse reactions, those reported by at least 2% of people, as headache, indigestion (dyspepsia), back pain, muscle aches (myalgia), nasal congestion, flushing and pain in a limb. [1] In general, these effects were dose dependent, short-lived and mostly mild or moderate. [6]
Other effects that show up in drug references include nausea, diarrhea and dizziness. [6] If one of these bothers you, it is worth telling your clinician rather than quietly stopping or changing your dose.
How often did these side effects happen in trials?
The numbers below come from placebo-controlled clinical trials of FDA-approved tadalafil tablets taken as needed. They describe what the trials found, not what any one person will feel. Individual results vary.
| Side effect | Placebo | 5 mg | 10 mg | 20 mg |
|---|---|---|---|---|
| Headache | 5% | 11% | 11% | 15% |
| Indigestion | 1% | 4% | 8% | 10% |
| Back pain | 3% | 3% | 5% | 6% |
| Muscle aches | 1% | 1% | 4% | 3% |
| Nasal congestion | 1% | 2% | 3% | 3% |
Source: tadalafil tablet label, clinical trials experience. [1]
Two things stand out. First, headache and indigestion rose as the dose went up, which fits the label's description of dose-dependent effects. Second, placebo groups also reported headaches and back pain, so not every symptom is caused by the medicine.
For the lower once-daily doses, the label reports smaller numbers. In 12-week studies, headache was reported by 3% of people taking 2.5 mg and 6% taking 5 mg, compared with 5% on placebo. Indigestion was 4% and 5% versus 2% on placebo. [2]
When do side effects start, and how long do they last?
One drug reference notes that side effects are often most noticeable within a few hours of a dose, when the level of medicine in the blood is highest. Back pain and muscle aches can appear later, around 12 to 24 hours after a dose. [6]
Because tadalafil stays in the body for a long time, a side effect can linger longer than people expect. That is one reason clinicians ask you not to take extra doses. Our post on the maximum dose of tadalafil in 24 hours explains what the label says about dosing limits.
Side effects of tadalafil on long-term use
Many people search for "tadalafil side effects long term" because some clinicians prescribe a low once-daily dose. The honest answer is that the label reports safety data from trials lasting weeks to about a year, not decades. [2]
Here is what those longer trials show:
- Same kinds of effects. In a 24-week study period and a 1-year open-label extension described in the label, the reported effects were of the same type as in shorter trials, such as back pain and muscle aches. In the extension, back pain was reported by 5.5% of people and muscle aches by 1.3%. [1], [2]
- Stopping because of side effects. In three 12-week trials of once-daily use in men with BPH, or ED and BPH (average age 63), 3.6% of those on tadalafil stopped because of adverse events, compared with 1.6% on placebo. The reasons included headache, upper abdominal pain and muscle aches. [3]
- Vision and hearing. One drug reference lists vision loss and hearing loss as the things worth knowing about if you take tadalafil for a long time. [6] Both are rare and are covered in the next section.
Long-term use also means your health can change around the medicine. New heart conditions, new medicines (especially nitrates) or eye and hearing changes can all affect whether tadalafil is still appropriate. That is why regular check-ins with a clinician matter more than any single number.
Serious side effects: when to get help right away
Serious reactions are uncommon, but they need fast action. Stop taking tadalafil and get medical help for any of the following. [5]
| Symptom | Why it matters | What to do |
|---|---|---|
| Erection lasting longer than 4 hours (painful or not) | Priapism can cause permanent damage to erectile tissue if not treated promptly. [4] | Seek emergency care |
| Sudden loss or decrease of vision in one or both eyes | Vision loss was permanent in some cases, and it is not known whether the medicine caused it. [5] | Stop tadalafil, get emergency care |
| Sudden decrease or loss of hearing, sometimes with ringing or dizziness | Reported after tadalafil and similar medicines. [5] | Stop tadalafil, call your doctor right away |
| Chest pain, fainting or severe dizziness | Can signal very low blood pressure or a heart problem. [5] | Get emergency care |
| Hives, rash, swelling of the face or throat, trouble breathing | Signs of a serious allergic reaction. [5] | Get emergency care |
A closer look at vision and hearing
Some people have a brief change in how they see colors, such as trouble telling blue from green. The label notes that PDE inhibitors cause a temporary, dose-related change in color discrimination, with the peak effect near the time of peak blood levels. [4] That is different from sudden vision loss, which is an emergency.
In the small number of people who lost vision suddenly after taking medicines like tadalafil, most already had eye problems or risk factors for blood vessel disease. Those include heart disease, diabetes, high blood pressure, high cholesterol, smoking or being over 50. It is not clear whether the medicine was the cause. [7] Tell your clinician about any eye history before you start.
Who is at higher risk of a long erection?
People with sickle cell anemia, multiple myeloma, leukemia, or a curved or scarred penis, such as Peyronie's disease, may be at higher risk of priapism. [6] If any of these apply to you, say so during your health assessment.
Who should not take tadalafil
Some people should not take tadalafil, and some medicines do not mix with it. A licensed clinician will review your history, but you should know the big ones:
- Nitrates. Never take tadalafil with nitrate medicines for chest pain or heart problems, such as nitroglycerin or isosorbide. Together they can cause a sudden, serious drop in blood pressure. [7]
- "Poppers." Recreational drugs that contain amyl nitrite or butyl nitrite count as nitrates. Tell your clinician if you use them. [5]
- Riociguat. This medicine for pulmonary hypertension should not be combined with tadalafil. [7]
- Certain other prescriptions. Some HIV medicines, oral antifungals and antibiotics can raise tadalafil levels in the blood, which may lead to low blood pressure, dizziness, fainting, priapism or vision problems. [8]
- Heavy alcohol use. The label says substantial drinking, about 5 units or more, together with tadalafil can increase dizziness, headache, a faster heart rate and a drop in standing blood pressure. [1]
This list is not complete. Always give your clinician and pharmacist a full list of prescriptions, over-the-counter products and supplements.
A note on compounded tadalafil pills
Some tadalafil pills offered through telehealth are compounded by a licensed pharmacy. Compounded medications are not FDA-approved, and the FDA does not review compounded drugs for safety, effectiveness or quality. [9], [10]
That matters for this topic. The side-effect numbers in this article come from trials and labels for FDA-approved tadalafil tablets. They explain what is known about tadalafil as a medicine, but they are not test results for any specific compounded product. Our Powered Up Pill: tadalafil program is a compounded, prescription-only option, and a licensed clinician decides whether it is appropriate for you after reviewing your health assessment.
Practical steps if you are thinking about tadalafil
You can make a conversation with a clinician more useful by preparing a few things ahead of time.
- Write down every medicine you take. Include nitrates, blood pressure medicines, heart medicines, antifungals, HIV medicines, antibiotics and any recreational drugs.
- List your health history. Heart disease, low blood pressure, eye or hearing problems, sickle cell disease and Peyronie's disease are all worth mentioning.
- Keep a simple symptom note. Record the date, the dose, the symptom and when it started. Timing helps a clinician tell whether something is likely related.
- Know your emergency signs. An erection lasting more than 4 hours, sudden vision or hearing loss, chest pain or fainting all need urgent care.
- Report problems. You can report suspected side effects to the FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. [2]
Questions to ask a clinician
- Based on my health history, is tadalafil appropriate for me?
- Which side effects should I expect, and which mean I should stop and call?
- Does anything I take now interact with tadalafil?
- If I get headaches or back pain, should the dose or schedule change?
- How often should we review whether this is still the right treatment?
Frequently asked questions
What are the most common side effects of tadalafil?
The label lists headache, indigestion, back pain, muscle aches, nasal congestion, flushing and pain in the arms or legs. [1] In trials they were mostly mild or moderate and short-lived. [6] If they are strong or do not go away, talk to your clinician.
Do tadalafil side effects go away?
Often they do. Side effects tend to be most noticeable within hours of a dose, and back pain or muscle aches can show up 12 to 24 hours later. [6] Persistent or worsening symptoms should be reviewed by a clinician, and sudden vision or hearing changes should be treated as emergencies.
Are there long-term side effects of tadalafil?
The label reports trial data of up to about a year, and the effects seen were of the same types as in shorter studies. [2] Rare vision and hearing problems are the main things flagged for long-term users. [6] There is less information beyond that, so ongoing check-ins with a clinician are important.
Can tadalafil cause back pain and muscle aches?
Yes. In trials of as-needed use, back pain was reported by up to 6% of people and muscle aches by up to 4%, depending on the dose. [1] Tell your clinician if the pain is severe, because they may adjust your treatment.
Is it safe to drink alcohol with tadalafil?
The label warns that substantial alcohol intake, about 5 units or more, can increase dizziness, headache and a drop in standing blood pressure. [1] Ask your clinician what is reasonable for you.
When should I go to the emergency room?
Go if you have an erection lasting more than 4 hours, sudden vision loss, sudden hearing loss, chest pain, fainting, or signs of a serious allergic reaction. [4], [5]
Talk to a licensed clinician
Whether tadalafil is a good fit depends on your health, your medicines and your goals. At ShopMedRx, you complete an online health assessment, and an independent, licensed clinician reviews it and decides whether a prescription is appropriate. Prescriptions are not guaranteed. This service is for adults 18 and older.
Do not start, stop or change any medicine without talking to a licensed clinician. In an emergency, call 911.
Important information
- This article is for general education and is not medical advice. Talk to a licensed clinician before starting, stopping or changing any treatment.
- All medications available through ShopMedRx are prescription only and are prescribed only if appropriate after a licensed clinician's review.
- Some medications we offer are compounded. Compounded medications are not FDA-approved, and the FDA does not review compounded drugs for safety, effectiveness or quality before they are marketed. They are not the same as, or generic versions of, brand-name drugs.
- Individual results vary. Nothing in this article promises a specific result.
- Prescriptions are written by independent, licensed clinicians through OpenLoop Health and filled by licensed U.S. partner pharmacies.
Sources
- Tadalafil tablets: drug label information (adverse reactions, alcohol). DailyMed, U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=0b75f746-866e-3a5b-e063-6294a90a5e02
- Tadalafil: package insert / prescribing information (label text). Drugs.com. https://www.drugs.com/pro/tadalafil.html
- Tadalafil tablets, film coated: drug label information. DailyMed, U.S. National Library of Medicine. https://www.dailymed.nlm.nih.gov/dailymed/getFile.cfm?setid=e3aafacc-c392-4a0c-82ed-ef139e363732&type=pdf
- Tadalafil tablets: full prescribing information (2008 version; priapism and color discrimination). U.S. FDA. https://www.accessdata.fda.gov/drugsatfda_docs/label/2008/021368s011lbl.pdf
- Tadalafil: MedlinePlus drug information. National Library of Medicine. https://medlineplus.gov/druginfo/meds/a604008.html
- Tadalafil side effects: common, severe, long term. Drugs.com. https://www.drugs.com/sfx/tadalafil-side-effects.html
- Tadalafil: uses, dosage, side effects. Drugs.com. https://www.drugs.com/tadalafil.html
- Tadalafil (oral tablet): side effects, dosage, and review. Healthline. https://www.healthline.com/health/drugs/tadalafil-oral-tablet
- Understanding the risks of compounded drugs. U.S. FDA. https://www.fda.gov/drugs/human-drug-compounding/understanding-risks-compounded-drugs
- Human drug compounding. U.S. FDA. https://www.fda.gov/drugs/guidance-compliance-regulatory-information/human-drug-compounding