Introduction
Tadalafil helps treat several health issues, most commonly erectile dysfunction (ED). It belongs to a group of drugs called PDE5 inhibitors. People like tadalafil because it works longer than similar meds. The FDA approved it in 2003, and it has helped millions of people since then.
This guide covers what tadalafil does, how it works, how to use it safely, possible side effects, and key facts you should know. Whether you’re thinking about taking it or just curious, this guide has you covered.
What is Tadalafil?
Tadalafil is a prescription drug that blocks an enzyme called PDE5. The drug company Eli Lilly created it, and the FDA approved it in 2003. You might know it by the brand name Cialis® for ED treatment. For lung blood pressure issues, it’s sold as Adcirca®.
You can get tadalafil tablets in different strengths (2.5mg, 5mg, 10mg, and 20mg). Your doctor might prescribe it for daily use or just when needed.
Key Facts About Tadalafil:
- Works for a long time: Often called the “weekend pill,” it can work for up to 36 hours
- Now more affordable: Generic versions became available in 2018
- Treats multiple issues: Helps with ED, enlarged prostate, and lung blood pressure problems
FDA-Approved Uses
Erectile Dysfunction (ED)
ED means having trouble getting or keeping an erection firm enough for sex. Tadalafil was first made to treat this problem. Studies show it works much better than placebo pills for most men with ED, even those with diabetes or after prostate surgery.
Research in the Journal of Sexual Medicine found 81% of men reported better erections with tadalafil. Only 35% improved with placebo pills.
Enlarged Prostate (BPH)
BPH happens when the prostate gland grows larger as men age. This can cause frequent urination, weak urine flow, and waking up at night to pee.
The FDA approved tadalafil for BPH symptoms in 2011. A daily 5mg dose helps by relaxing muscles in the prostate and bladder. This improves urine flow and reduces symptoms.
Men who have both ED and BPH can benefit greatly from tadalafil. It treats both problems at once.
Pulmonary Arterial Hypertension (PAH)
PAH means high blood pressure in the arteries going to your lungs. This makes your heart work harder and can lead to heart failure if not treated.
For this condition, tadalafil is sold as Adcirca®. It works by relaxing blood vessels in the lungs so blood flows more easily. Studies show that taking 40mg daily helps patients exercise better and delays worsening of the disease.
How Tadalafil Works
To understand how tadalafil works, let’s look at what happens during an erection and in other conditions it treats.
How It Works in Your Body
Tadalafil mainly blocks an enzyme called PDE5. This enzyme breaks down a chemical messenger (cGMP) that relaxes muscles and increases blood flow.
Here’s the step-by-step process:
- Sexual arousal: When a man is sexually aroused, his body releases nitric oxide
- Chemical reaction: Nitric oxide triggers production of cGMP
- Muscle relaxation: cGMP relaxes the muscles in blood vessel walls
- Blood flow increase: More blood flows into the penis
- Tadalafil’s role: Tadalafil prevents the breakdown of cGMP, keeping its effects going longer
Important: Tadalafil doesn’t work without sexual arousal. It doesn’t cause automatic erections. It only enhances your natural response to sexual stimulation.
For Lung Conditions
In the lungs, tadalafil works similarly. It increases cGMP levels in lung blood vessels, helping them relax. This lowers pressure in these vessels and improves symptoms of PAH.
For Prostate Issues
For enlarged prostate symptoms, we’re still learning exactly how it works. Research suggests the increased cGMP helps relax muscles in the prostate and bladder area, which eases urinary symptoms.
Dosage and How to Take It
Your tadalafil dose depends on your health condition, how your body responds, your kidney and liver function, and other drugs you take. Always follow your doctor’s instructions.
For Erectile Dysfunction
As-needed dosing:
- Starting dose: Usually 10mg before sexual activity
- Range: 5-20mg based on how well it works and side effects
- How often: No more than once per day
- When to take: 30 minutes to 36 hours before sexual activity
Daily dosing:
- Starting dose: 2.5mg at the same time each day
- May increase to 5mg daily if needed
- Benefit: Allows for spontaneous sexual activity without planning
For Enlarged Prostate
- Recommended dose: 5mg once daily
- When to take: Same time each day
- Not for as-needed use
For Combined ED and BPH
- Recommended dose: 5mg once daily
- Treats both conditions at the same time
For Pulmonary Arterial Hypertension
- Recommended dose: 40mg (two 20mg tablets) once daily
- Don’t combine with other PDE5 inhibitors
How to Take It
- Can be taken with or without food
- Swallow whole with water, don’t crush or chew
- Avoid grapefruit juice as it can increase drug levels in your blood
- Limit alcohol as it may cause dizziness, headache, or low blood pressure
How Well It Works
For Erectile Dysfunction
Many clinical trials show tadalafil works well for ED:
- Analysis of 17 studies showed tadalafil improved erectile function for all ED severity levels
- It works for tough cases like diabetes, high blood pressure, and after prostate surgery
- Standard measures of erectile function showed big improvements compared to placebo
About 70-85% of men report better erections with tadalafil. Only 25-35% improve with placebo.
For Enlarged Prostate Symptoms
In clinical trials for BPH:
- Daily tadalafil (5mg) significantly improved prostate symptom scores
- Men saw improvements as early as 1-2 weeks after starting
- Benefits continued throughout treatment
- Studies showed average symptom score improvements of 4.8-5.6 points versus 2.3-3.6 points with placebo
For Pulmonary Arterial Hypertension
For PAH treatment:
- The PHIRST study showed significant improvements in walking distance
- Patients taking tadalafil 40mg daily walked an average of 33 meters farther than those on placebo
- Treatment delayed disease worsening by 68% compared to placebo
- Quality of life measures showed clear improvement
Side Effects and Safety
Most people tolerate tadalafil well, but like all medicines, it can cause side effects. Knowing these helps you make informed choices and know when to call your doctor.
Common Side Effects
Most common side effects include:
- Headache (10-15% of users)
- Indigestion (6-10%)
- Back pain (6-9%)
- Muscle aches (3-7%)
- Stuffy nose (2-5%)
- Flushing or warmth in the face (2-3%)
These side effects are usually mild to moderate. Most go away within a few hours as your body adjusts to the medicine.
Less Common Side Effects
- Dizziness
- Blurred vision
- Changes in color vision
- Light sensitivity
- Ringing in ears
- Nausea
- Skin rash
Rare but Serious Side Effects
Some rare but serious side effects need immediate medical attention:
- Prolonged erection: A painful erection lasting more than 4 hours can cause permanent damage if not treated quickly
- Sudden vision loss: May indicate a serious eye problem
- Sudden hearing loss: Sometimes with ringing in ears and dizziness
- Low blood pressure: Especially when combined with certain other drugs
- Heart problems: Including heart attack, stroke, or irregular heartbeat (rare, typically in people with existing heart risks)
Safety for Special Groups
Older adults: Generally safe, but lower starting doses may be recommended
People with kidney problems:
- Mild to moderate kidney disease: May need dose adjustment
- Severe kidney disease: Use with caution; maximum dose typically limited to 10mg for as-needed use or 2.5mg for daily use
People with liver problems:
- Mild to moderate liver disease: Maximum recommended dose is 10mg
- Severe liver disease: Not recommended
Drug Interactions and Warnings
Do Not Take Tadalafil If You:
- Take nitrate drugs (like nitroglycerin) for chest pain
- Use recreational drugs called “poppers” (amyl nitrite, butyl nitrite)
- Had a heart attack in the last 90 days
- Have unstable chest pain
- Have severe heart failure or heart rhythm problems
- Had a stroke in the last 6 months
- Have very low blood pressure (below 90/50) or uncontrolled high blood pressure (above 170/100)
- Have a rare eye disorder called retinitis pigmentosa
- Have ever had sudden vision loss from poor blood flow to the eye
Use With Caution If You Have:
- Penis deformity (like Peyronie’s disease)
- Conditions that might cause prolonged erections (sickle cell anemia, multiple myeloma, leukemia)
- Active stomach ulcers
- Bleeding disorders or active bleeding
- Significant heart disease
Important Drug Interactions
Nitrates: Can cause dangerous drop in blood pressure
Alpha-blockers (drugs for high blood pressure or prostate):
- Can lower blood pressure too much
- Should be on stable dose before starting tadalafil
- Start with lowest tadalafil dose (2.5mg)
- Tamsulosin (0.4mg) seems to have less interaction risk
Drugs that affect tadalafil metabolism:
- Strong inhibitors (ketoconazole, ritonavir): Can increase tadalafil levels; maximum dose typically 10mg every 72 hours
- Moderate inhibitors (erythromycin, grapefruit juice): May require lower doses
Drugs that reduce tadalafil effectiveness (rifampin, phenytoin, carbamazepine)
Other PDE5 inhibitors: Don’t combine due to increased side effect risk
Alcohol: May increase risk of dizziness, headache, and low blood pressure
Off-Label Uses
Doctors sometimes prescribe tadalafil for conditions not FDA-approved. Research suggests possible benefits for:
Raynaud’s Phenomenon
This condition causes blood vessels in fingers and toes to narrow too much in cold or stress. Small studies show tadalafil may improve blood flow and reduce attack frequency and severity.
Research in the Journal of Rheumatology found tadalafil reduced Raynaud’s attacks and improved blood flow in patients with related conditions.
Exercise at High Altitude
Some research suggests tadalafil may help counteract high-altitude effects on lung blood pressure. This could improve exercise capacity at high elevations. A study in the Annals of Internal Medicine showed tadalafil reduced lung artery pressure and improved exercise capacity in healthy volunteers at simulated high altitude.
Female Sexual Problems
Results have been mixed, but some studies looked at tadalafil for female sexual arousal disorder, especially in women with reduced genital blood flow. Research is still early, and tadalafil is not approved for women.
Lymphatic Issues
Early research suggests PDE5 inhibitors might help manage certain lymphatic vessel problems, though this remains experimental.
Remember: Off-label use should only happen under doctor supervision after discussing risks and benefits.
Patient Experiences
Based on surveys and clinical trial feedback, here’s what patients typically report:
For Erectile Dysfunction
Most users like tadalafil because:
- It works for a long time (“weekend pill”)
- Less pressure to time sexual activity
- More spontaneity than shorter-acting options
- Less performance anxiety due to reliable results
Common challenges include:
- Cost concerns (though better with generic versions)
- Side effects like headache and muscle pain
- Need for ongoing prescriptions
For Enlarged Prostate
Patients typically report:
- Gradual improvement in urinary symptoms over weeks
- Appreciation for dual benefit if they have both ED and BPH
- Sometimes less noticeable improvement than what measurements show
For PAH
Patients with PAH often note:
- Better exercise tolerance and daily function
- Improved quality of life with less shortness of breath
- Convenience of pill form compared to other treatments
Comparing to Similar Medicines
Tadalafil vs. Other PDE5 Inhibitors
Sildenafil (Viagra®):
- Starts working: 30-60 minutes vs. tadalafil’s 30-45 minutes
- Works for: 4-5 hours vs. tadalafil’s 24-36 hours
- Food effects: High-fat meal delays sildenafil; minimal effect on tadalafil
- Dosing: As-needed only vs. tadalafil’s daily or as-needed options
- Visual side effects: More common with sildenafil
- Approved uses: ED and PAH vs. tadalafil’s ED, BPH, and PAH
Vardenafil (Levitra®):
- Starts working: 25-60 minutes (similar to tadalafil)
- Works for: 4-5 hours (shorter than tadalafil)
- Food effects: High-fat meal reduces effectiveness; minimal effect on tadalafil
- Visual side effects: Less common than sildenafil but more common than tadalafil
- Approved uses: ED only vs. tadalafil’s multiple approvals
Avanafil (Stendra®):
- Starts working: 15-30 minutes (potentially faster than tadalafil)
- Works for: 6 hours (shorter than tadalafil)
- Food effects: Minimal (similar to tadalafil)
- Fewer drug interactions than others
- Approved uses: ED only vs. tadalafil’s multiple approvals
For Enlarged Prostate Treatment Comparison
Versus Alpha-blockers (tamsulosin, alfuzosin):
- Alpha-blockers relieve symptoms faster (days vs. weeks)
- Similar overall effectiveness after several weeks
- Different side effects (ejaculation problems more common with alpha-blockers)
- Tadalafil offers dual benefit for men with both ED and BPH
Versus 5-alpha reductase inhibitors (finasteride, dutasteride):
- These drugs reduce prostate size and disease progression
- Take longer to work (3-6 months)
- May cause sexual side effects (reduced desire, ED)
- Different mechanisms (can work well together)
For PAH Treatment Comparison
Versus other PDE5 inhibitors:
- Longer half-life allows once-daily dosing (vs. three times daily for sildenafil)
- Similar effectiveness in improving exercise capacity
- Similar safety profiles
Versus other PAH drug classes:
- Prostacyclins typically work better but require complex delivery systems
- Endothelin receptor antagonists comparable in pill form convenience
- PDE5 inhibitors generally have fewer side effects
- Often used in combination for better results
Special Considerations
Women and Tadalafil
Tadalafil is not FDA-approved for women. Limited research on women with sexual arousal disorders shows mixed results. Female sexual response differs from men’s, which may explain the variable results.
Pregnant women should not take tadalafil. Safety during pregnancy has not been established.
Children and Teens
Tadalafil is not for people under 18 years old. Some research exists on its use in children with PAH, but more study is needed before making recommendations.
Recreational Use
Some people without ED use tadalafil recreationally, sometimes with other substances. This practice has several risks:
- May mask underlying ED causes that need medical attention
- Possible psychological dependence
- Dangerous interactions with recreational drugs, especially “poppers”
- May contribute to risky sexual behavior
- Increased risk of STIs
Doctors stress that tadalafil is a prescription medicine only for diagnosed conditions under medical supervision.
Future Research
Current and upcoming research on tadalafil includes:
New Uses
- Duchenne muscular dystrophy: Early studies suggest possible heart function benefits
- Diabetic nerve damage: Research on effects on nerve function and blood flow
- Brain function: Early research exploring potential brain benefits
New Forms
- Combination pills with other agents for BPH or ED
- Topical forms for local effects with fewer whole-body side effects
- Modified-release forms for optimized delivery
Personalized Medicine Research
Studies looking at genetic and body markers that might predict:
- Which patients will respond best
- Who might get side effects
- Best dosing strategies for individuals
Tips for Patients
Getting Best Results
- For erectile dysfunction: Take as directed for as-needed use, typically 30 minutes to 12 hours before sex. For daily use, take at the same time each day.
- For enlarged prostate: Consistency matters—take your daily dose at the same time each day. Give the medicine several weeks to reach full effect.
- For PAH: Follow your prescribed schedule exactly; try not to miss doses.
Saving Money
- Insurance: Check if your health insurance covers tadalafil and what your copay is.
- Generic options: Generic tadalafil costs much less than brand names and works the same.
- Patient assistance: Drug makers sometimes offer help programs for eligible patients.
- Savings programs: Many online and retail pharmacies offer discounts on generic tadalafil.
Lifestyle Tips
Get the most from tadalafil by:
- Exercising regularly to keep blood vessels healthy
- Eating plenty of fruits, vegetables, and whole grains
- Limiting alcohol
- Not smoking
- Managing stress
- Keeping regular doctor appointments
Common Questions
Q: How quickly does tadalafil work?
A: For erectile dysfunction, tadalafil usually starts working within 30-45 minutes. Some men notice effects in 16-30 minutes. For enlarged prostate, symptom improvement usually begins within 1-2 weeks but may take up to 4 weeks for full effect.
Q: Can I take tadalafil daily?
A: Yes, tadalafil is approved for daily use in lower doses (2.5mg or 5mg) for both erectile dysfunction and enlarged prostate. Daily dosing keeps a steady level in your body, allowing for spontaneous sexual activity.
Q: Does tadalafil work for everyone?
A: Tadalafil helps most patients, but not everyone. About 70-85% of men with erectile dysfunction respond to tadalafil. The other 15-30% may need different treatments. Success rates vary based on what’s causing the ED. Complex cases like after prostate surgery or severe diabetes may have lower success rates.
Q: Can women take tadalafil?
A: Tadalafil is not FDA-approved for women. Some research has looked at its use for female sexual arousal disorders, but results are mixed. Safety for women has not been fully established.
Q: Will tadalafil affect my fertility?
A: Current evidence suggests tadalafil does not harm male fertility. Some studies even show potential benefits for certain fertility factors, though tadalafil is not prescribed to enhance fertility.
Q: Is it safe to buy tadalafil online?
A: Only buy tadalafil from licensed pharmacies with a valid prescription. Online sources without proper pharmacy credentials may sell fake or contaminated products that can be dangerous. Always talk to a healthcare provider before starting tadalafil.
Q: How long can I safely take tadalafil?
A: Tadalafil has been studied for long-term use with a good safety record. Many patients take it for years without developing tolerance or new side effects. Regular check-ups with your doctor are recommended to monitor your health status.
Q: Can I drink alcohol while taking tadalafil?
A: Moderate alcohol (1-2 drinks) usually doesn’t significantly interact with tadalafil. However, excessive alcohol may increase dizziness when standing, headaches, and increased heart rate. Alcohol can also independently worsen erectile function.
Conclusion
Tadalafil has proven to be a versatile and effective medicine for several conditions, especially erectile dysfunction, enlarged prostate, and pulmonary arterial hypertension. Its long-lasting action and daily dose option give it unique advantages over similar drugs.
Like all medicines, tadalafil has potential risks and side effects that must be weighed against its benefits. Your overall health, other medications, and personal preferences all matter when deciding if tadalafil is right for you.
Research on tadalafil continues to grow, exploring new uses and better treatment approaches. With generic versions now widely available, cost barriers have decreased for many patients.
If you’re considering tadalafil, talk with a healthcare provider to ensure safe and effective use tailored to your needs. With proper medical guidance, tadalafil can significantly improve quality of life for many people.