Tadalafil Side Effects: What's Common and What's Serious

Tadalafil is widely prescribed in the UK for erectile dysfunction and benign prostatic hyperplasia, but like all medicines, it can cause side effects. Most people who take tadalafil experience no problems at all, whilst others may notice mild reactions. Understanding what’s normal and what requires medical attention helps you use this medication safely.

This guide explains the side effects of tadalafil based on clinical data and UK prescribing information. It is for informational purposes only and does not constitute medical advice. Always follow your prescriber’s instructions and consult a healthcare professional if you have concerns.

How Common Are Side Effects?

Clinical trials and post-marketing surveillance show that most people tolerate tadalafil well. The frequency and severity of side effects can vary based on the dose, how often you take it, and your individual health profile.

Side effects are typically categorised as:

• Very common: Affecting more than 1 in 10 people
• Common: Affecting up to 1 in 10 people
• Uncommon: Affecting up to 1 in 100 people
• Rare: Affecting up to 1 in 1,000 people
• Very rare: Affecting fewer than 1 in 10,000 people

The majority of tadalafil side effects, when they occur, are mild and temporary.

Common Side Effects

These are the reactions most frequently reported by people taking tadalafil:

Headaches

Headache is one of the most commonly reported side effects of tadalafil. This occurs because the medication dilates blood vessels throughout the body, not just in the genital area. The headache is usually mild to moderate and often improves as your body adjusts to the medication.

Many prescribers suggest staying well-hydrated and considering a mild painkiller if needed, though you should check with your doctor or pharmacist about which painkillers are suitable to take with tadalafil.

Indigestion and Heartburn

Tadalafil can relax the muscles in the oesophagus, occasionally leading to acid reflux symptoms. People report a burning sensation in the chest or stomach discomfort, particularly if they take tadalafil on an empty stomach or lie down shortly after taking it.

Taking tadalafil with food may help reduce these symptoms for some people, though this is something to discuss with your prescriber.

Facial Flushing

A warm, red flush across the face and neck is another common reaction. This happens due to increased blood flow near the skin’s surface and typically fades within a few hours. Whilst noticeable, facial flushing is generally harmless.

Nasal Congestion

Some people experience a stuffy or runny nose after taking tadalafil. This is caused by the same blood vessel dilation that helps the medication work for its intended purpose. The congestion is usually mild and temporary.

Back Pain and Muscle Aches

Tadalafil can sometimes cause discomfort in the back or muscles, particularly in the lower back and thighs. This typically appears 12 to 24 hours after taking the medication and resolves within 48 hours without treatment.

The exact mechanism isn’t fully understood, but it’s thought to relate to how tadalafil affects muscle cells. If back pain or muscle aches persist or become severe, contact your prescriber.

Dizziness

Some people feel lightheaded or dizzy, especially when standing up quickly. This is because tadalafil can lower blood pressure slightly. If you experience dizziness, sit or lie down until it passes, and mention it to your doctor at your next appointment.

Less Common Side Effects

The following reactions occur less frequently but are still worth being aware of:

• Nausea or stomach upset
• Vision changes, such as blurred vision or increased sensitivity to light
• Changes in colour vision (seeing a blue tinge)
• Ringing in the ears (tinnitus)
• Irregular heartbeat or palpitations
• Swelling in the hands, feet, or ankles

If you notice any of these symptoms and they concern you, speak with a healthcare professional.

Serious Side Effects Requiring Immediate Medical Attention

Whilst rare, some side effects require urgent medical care. Seek immediate help if you experience:

Prolonged Erection (Priapism)

An erection lasting more than four hours is a medical emergency. Priapism can damage penile tissue permanently if not treated promptly. If you have an erection that won’t go away, go to A&E or call 999 immediately.

Sudden Vision Loss

Sudden decrease or loss of vision in one or both eyes requires immediate medical attention. This could indicate a serious condition called non-arteritic anterior ischaemic optic neuropathy (NAION). Stop taking tadalafil and seek emergency care.

For more information about visual side effects, see our guide on tadalafil eye side effects.

Sudden Hearing Loss

Sudden decrease or loss of hearing, sometimes accompanied by ringing in the ears or dizziness, needs urgent evaluation. Stop taking tadalafil and contact a doctor immediately.

Chest Pain or Irregular Heartbeat

If you experience chest pain, particularly during sexual activity, stop what you’re doing and seek medical help. Never take nitrate medications (often prescribed for angina) if you’ve recently taken tadalafil, as the combination can cause a dangerous drop in blood pressure.

Severe Allergic Reactions

Although very rare, allergic reactions can include difficulty breathing, swelling of the face, lips, tongue, or throat, and severe skin rashes. These require immediate emergency treatment.

Severe Skin Reactions

Serious skin reactions such as Stevens-Johnson syndrome are extremely rare but serious. Symptoms include widespread rash, peeling skin, and blisters. Stop taking tadalafil and seek immediate medical care if you develop a severe skin reaction.

Factors That May Increase Side Effects

Several factors can influence whether you experience side effects and how severe they might be:

Dose and Frequency

Higher doses of tadalafil (20 mg versus 5 mg) generally carry a higher risk of side effects. Daily dosing may also affect how your body responds compared with on-demand use.

Your prescriber will consider the appropriate dose based on your needs and health profile. Never adjust your dose without medical guidance.

Alcohol Consumption

Drinking alcohol whilst taking tadalafil can increase the likelihood of side effects such as dizziness, headache, and low blood pressure. Moderate alcohol consumption is generally considered safe for most people, but excessive drinking should be avoided.

For detailed information, read our article on tadalafil, alcohol and blood pressure.

Other Medications

Tadalafil can interact with numerous medications, potentially increasing side effects or reducing effectiveness. This includes:

• Nitrates (used for chest pain)
• Alpha-blockers (used for prostate problems or high blood pressure)
• Other blood pressure medications
• Some antifungal medications
• Certain antibiotics
• HIV medications

Always inform your prescriber about all medications you take, including over-the-counter drugs and supplements.

Underlying Health Conditions

Pre-existing conditions can affect how you respond to tadalafil:

• Heart disease or cardiovascular problems
• High or low blood pressure
• Liver or kidney disease
• Stomach ulcers
• Blood cell disorders
• Eye conditions, particularly retinitis pigmentosa

Your prescriber will assess whether tadalafil is suitable given your medical history.

Managing Side Effects

If you experience mild side effects, these strategies may help:

Headaches

Stay hydrated, consider a mild painkiller (check with your pharmacist first), and give your body time to adjust. Headaches often lessen after the first few doses.

Indigestion

Take tadalafil with food, avoid lying down immediately after taking it, and consider antacids if appropriate. Discuss persistent indigestion with your doctor.

Nasal Congestion

A saline nasal spray may provide relief without interfering with tadalafil. Avoid decongestants unless approved by your doctor, as some can interact with tadalafil.

Back Pain and Muscle Aches

Gentle stretching, a warm bath, and over-the-counter pain relief (if suitable) can help. These symptoms typically resolve on their own within a couple of days.

Dizziness

Rise slowly from sitting or lying positions, avoid sudden movements, and stay hydrated. If dizziness persists or worsens, consult your prescriber.

When to Contact Your Doctor

You should speak with a healthcare professional if:

• Side effects are severe or don’t improve
• You experience new or unexpected symptoms
• Side effects interfere with your daily life
• You’re concerned about any reaction you’re experiencing
• You want to discuss adjusting your dose or trying an alternative medication

Your prescriber may recommend a lower dose, suggest taking tadalafil differently, or consider an alternative treatment.

Long-Term Side Effects

For people taking tadalafil regularly over months or years, understanding long-term safety is important. Current evidence suggests that tadalafil is generally safe for long-term use when prescribed and monitored appropriately.

However, any medication taken long-term should involve periodic review with your healthcare provider. Read more in our article on tadalafil long-term use and safety.

Comparing Side Effects with Other ED Medications

Tadalafil’s side effect profile is similar to other PDE5 inhibitors, though there are some differences. For instance, visual disturbances appear to be more common with sildenafil (Viagra), whilst back pain and muscle aches may be slightly more frequent with tadalafil.

For a detailed comparison, see our guides on tadalafil vs sildenafil and tadalafil vs other ED medicines.

Understanding the Patient Information Leaflet

Every pack of tadalafil comes with a patient information leaflet (PIL) that lists all known side effects. This document is comprehensive and can appear overwhelming, as it must include even very rare reactions.

Don’t be alarmed if you see a long list of potential side effects. The leaflet is designed to inform you of all possibilities, no matter how uncommon. Most people take tadalafil without experiencing significant problems.

Reporting Side Effects

If you experience a side effect not mentioned in the patient information leaflet, or if any side effect becomes serious, you can report it through the UK’s Yellow Card Scheme. This helps regulators and manufacturers monitor medication safety.

You can report side effects:

• Online at: https://yellowcard.mhra.gov.uk
• By phone: 0800 731 6789
• Through your doctor or pharmacist

Reporting suspected side effects helps improve our understanding of how medications affect real-world patients.

The Importance of Proper Medical Supervision

Tadalafil is a prescription-only medication in the UK for good reason. A qualified prescriber can:

• Assess whether tadalafil is appropriate for you
• Determine the correct dose
• Monitor for side effects and interactions
• Adjust treatment if needed
• Provide guidance on managing any reactions

Never take tadalafil without proper medical supervision. Purchasing from unlicensed sources carries serious risks, including receiving counterfeit medication that could be dangerous.

For guidance on obtaining tadalafil safely, see our article on how to buy tadalafil online in the UK.

Frequently Asked Questions

Can I take painkillers with tadalafil?

Many over-the-counter painkillers such as paracetamol or ibuprofen are generally considered safe to take with tadalafil, but you should check with your pharmacist first. Some medications can interact or compound side effects.

Will side effects go away if I keep taking tadalafil?

Many mild side effects, particularly headaches and facial flushing, often lessen as your body adjusts to the medication. This typically happens within a few days to a couple of weeks. If side effects persist or worsen, consult your prescriber.

Does a lower dose mean fewer side effects?

Generally, yes. Lower doses of tadalafil tend to cause fewer and less severe side effects. However, the dose must still be effective for your condition. Your prescriber will help find the right balance between effectiveness and tolerability.

Are side effects worse with daily tadalafil compared to on-demand use?

Not necessarily. Daily low-dose tadalafil may actually result in fewer noticeable side effects for some people because the drug level in your body remains more constant. However, individual responses vary.

What should I do if I experience an allergic reaction?

If you develop signs of a severe allergic reaction (difficulty breathing, swelling of the face or throat, severe rash), call 999 or go to A&E immediately. For mild reactions such as a minor rash, contact your doctor as soon as possible.

Can side effects indicate that the medication is working?

Side effects like facial flushing or headaches occur due to the same blood vessel dilation mechanism that allows tadalafil to work. However, the presence or absence of side effects doesn’t reliably indicate whether the medication will be effective for your condition.

Conclusion

Whilst tadalafil can cause side effects, most are mild and temporary. Serious reactions are rare, and many people take tadalafil without any problems at all. The key is to use the medication under proper medical supervision, be aware of what to watch for, and know when to seek help.

If you’re considering tadalafil or currently taking it and have concerns about side effects, speak with your prescriber. They can assess your individual situation and help ensure you’re using the medication as safely and effectively as possible.

Remember, this information is educational and should not replace professional medical advice. For personalised guidance about tadalafil side effects, always consult a qualified healthcare professional.