Tadalafil and Lorazepam: Can You Take Them Together?

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What is tadalafil and lorazepam used for?

Tadalafil is a prescription medicine used to treat erectile dysfunction (ED) in men. It belongs to a group of medicines called PDE5 inhibitors, which work by relaxing blood vessels in the penis, allowing increased blood flow when you are sexually aroused [4]. Tadalafil is available in two forms: on-demand tablets (10mg or 20mg taken at least 30 minutes before sex, with effects lasting up to 36 hours) and daily low-dose tablets (2.5mg or 5mg taken once a day). Tadalafil is the active ingredient in Cialis and is also available as a lower-cost generic.

Lorazepam is a benzodiazepine medicine prescribed for short-term relief of severe anxiety, sleep problems, or as a pre-medication before medical procedures. It works by enhancing the calming effects of a natural chemical in the brain called GABA. Lorazepam can cause drowsiness, dizziness, muscle relaxation, and reduced alertness. It is usually prescribed for short periods because long-term use can lead to dependence. If you have been prescribed lorazepam, it is important to tell your prescriber when requesting ED treatment, so they can check that the combination is suitable for you.

Is there an interaction between tadalafil and lorazepam?

There is no major direct pharmacological interaction between tadalafil and lorazepam—they work on different systems in the body and do not significantly affect each other's breakdown or activity. However, both medicines can cause similar side effects, particularly dizziness, drowsiness, and a drop in blood pressure. When taken together, these effects may add up, making you feel more light-headed or unsteady than you would with either medicine alone.

Tadalafil can lower blood pressure slightly, especially when you stand up quickly, because it relaxes blood vessels throughout the body [4]. Lorazepam can also cause dizziness and drowsiness, and may affect your coordination and reaction times. If you take both medicines on the same day—for example, lorazepam for anxiety in the evening and tadalafil before sexual activity—you should be aware that you may feel more drowsy or dizzy than usual. This is not dangerous for most people, but it does mean you should take extra care, especially if you need to drive, operate machinery, or perform tasks that require full alertness.

How the medicines work in your body

Tadalafil works by blocking an enzyme called PDE5, which normally breaks down a substance that keeps blood vessels relaxed. By blocking PDE5, tadalafil helps blood vessels in the penis stay open longer, making it easier to get and keep an erection when you are sexually stimulated [4]. Lorazepam, on the other hand, enhances the activity of GABA, a neurotransmitter that slows down brain activity, producing a calming effect. Because these medicines act on completely different pathways, they do not interfere with each other's main actions. The concern is simply that their side effects—particularly on blood pressure and alertness—can overlap.

When to get urgent help

• Erection lasting longer than 4 hours (priapism)—go to A&E or call 999 immediately
• Sudden loss of vision in one or both eyes—stop tadalafil and seek urgent medical help
• Sudden decrease or loss of hearing, possibly with ringing in the ears or dizziness—stop tadalafil and see a doctor urgently
• Chest pain during or after sex—stop activity, rest, and call 999 if pain does not go away quickly
• Severe dizziness, fainting, or very fast or irregular heartbeat—lie down and seek medical advice

Call 999 or go to A&E in an emergency, or contact NHS 111 for urgent advice.

What does your prescriber check before prescribing tadalafil and lorazepam together?

When you request tadalafil through an online consultation at Cured Pharmacy, you will be asked to list all your current medicines, including lorazepam and any other prescription or over-the-counter treatments. A UK-registered prescriber will review your answers to check that tadalafil is safe and suitable for you. They will look at your overall health, any other conditions you have (such as heart problems, low blood pressure, or liver or kidney disease), and whether any of your medicines could interact with tadalafil.

If you are taking lorazepam, the prescriber will consider whether you are at higher risk of side effects such as dizziness or drowsiness. They may advise you to start on a lower dose of tadalafil, or to avoid taking both medicines close together in time. For example, if you take lorazepam at night to help you sleep, and you plan to use tadalafil earlier in the evening, the prescriber may suggest allowing a few hours between doses to reduce the chance of feeling too drowsy or dizzy. The prescriber will also check that you do not have any absolute contraindications to tadalafil, such as taking nitrates, nicorandil, riociguat, or another PDE5 inhibitor—these combinations can cause a dangerous drop in blood pressure and must never be used together [4].

Practical advice for taking tadalafil and lorazepam safely

If your prescriber has confirmed that it is safe for you to take tadalafil and lorazepam, there are some practical steps you can take to minimise side effects. First, be aware of how each medicine affects you individually before combining them. If you are new to lorazepam, take it for a few days and notice any drowsiness or dizziness before adding tadalafil. Similarly, if you are starting tadalafil, try it on its own first (if possible) to see how your body responds.

Avoid drinking alcohol when you plan to take tadalafil, especially if you are also taking lorazepam. Alcohol can make dizziness and drowsiness worse, and it can also impair your ability to get an erection [1]. Stand up slowly from sitting or lying down, particularly after taking either medicine, to reduce the risk of feeling faint. If you feel very dizzy, light-headed, or unwell after taking both medicines, sit or lie down until the feeling passes, and contact your GP or pharmacist for advice.

Do not drive or operate heavy machinery if you feel drowsy or less alert than usual. Lorazepam can affect your reaction times and coordination, and adding tadalafil may increase these effects. If you experience any unexpected or severe side effects—such as a prolonged erection lasting more than four hours, sudden loss of vision or hearing, or chest pain during sex—seek urgent medical help immediately.

Timing your doses

If you take lorazepam regularly (for example, at bedtime), you may wish to use tadalafil earlier in the day or evening, allowing a gap of a few hours between the two medicines. On-demand tadalafil (10mg or 20mg) should be taken at least 30 minutes before sexual activity, and its effects can last up to 36 hours [4]. If you take lorazepam occasionally (for example, only when you feel very anxious), try to plan ahead so that you are not taking both medicines at exactly the same time. Your prescriber or pharmacist can give you personalised advice based on your routine and the doses you are taking.

At a glance

What are the warning signs to watch for with tadalafil and lorazepam?

Most men who take tadalafil and lorazepam together do not experience serious problems, but it is important to know the warning signs that need urgent attention. If you develop an erection that lasts longer than four hours (priapism), you must go to A&E or call 999 immediately. Priapism is a medical emergency that can cause permanent damage to the penis if not treated quickly. This is a rare side effect of tadalafil, but it can happen regardless of whether you are taking other medicines [4].

Sudden loss of vision in one or both eyes, or sudden decrease or loss of hearing (which may be accompanied by ringing in the ears or dizziness), are also rare but serious side effects of PDE5 inhibitors. If you notice any sudden change in your vision or hearing, stop taking tadalafil and seek medical help straight away [4]. If you experience chest pain during or after sex, do not continue sexual activity—sit down, rest, and call 999 if the pain does not go away quickly. Chest pain during sex can be a sign of a heart problem, and you should not take another dose of tadalafil until you have been assessed by a doctor.

Severe dizziness, fainting, or a very fast or irregular heartbeat may indicate that your blood pressure has dropped too low. This is more likely if you are also taking other medicines that lower blood pressure, or if you drink alcohol. If you feel faint or unwell, lie down with your legs raised and seek medical advice. Do not stop taking lorazepam suddenly without talking to your doctor, as this can cause withdrawal symptoms, especially if you have been taking it for more than a few weeks.

Can tadalafil and lorazepam affect erectile dysfunction itself?

Tadalafil is designed to help treat erectile dysfunction by improving blood flow to the penis, but it only works when you are sexually aroused—it does not increase sexual desire [4]. Lorazepam, on the other hand, can sometimes contribute to sexual difficulties. Benzodiazepines like lorazepam can reduce libido (sex drive), cause drowsiness, and make it harder to achieve or maintain an erection in some men. This does not happen to everyone, but if you notice that your ED has worsened since starting lorazepam, or if you feel less interested in sex, it is worth discussing this with your GP.

Anxiety itself is a common cause of erectile dysfunction, and lorazepam may be prescribed to help manage severe anxiety in the short term [1]. However, long-term use of benzodiazepines is not recommended, and your doctor may suggest other treatments for anxiety—such as talking therapies or antidepressants—that are less likely to affect sexual function. If you are taking lorazepam for anxiety and also experiencing ED, treating the underlying anxiety with appropriate long-term support may help improve your erections naturally, alongside the use of tadalafil when needed.

It is also important to remember that ED can be an early warning sign of other health problems, such as heart disease, diabetes, or high blood pressure [1]. If you have not already done so, see your GP for a full health check. Your GP can investigate the underlying causes of your ED and make sure that any other health conditions are being managed properly. Tadalafil can help with the symptoms of ED, but it does not treat the root cause, so a holistic approach to your health is important.

When to review your medicines

If you have been taking lorazepam for more than a few weeks, or if you feel that it is affecting your mood, energy, or sexual function, ask your GP to review your treatment. There may be alternative options that are more suitable for long-term use. Similarly, if tadalafil is not working as well as you hoped, or if you are experiencing side effects, your prescriber can adjust the dose or suggest a different PDE5 inhibitor, such as sildenafil, vardenafil, or avanafil. Every man responds differently to ED treatments, and it may take some trial and adjustment to find the best option for you.

In summary

• There is no major direct interaction between tadalafil and lorazepam, but both can cause dizziness and drowsiness.
• Always declare lorazepam and all other medicines in your online consultation so your prescriber can check safety.
• Avoid alcohol and stand up slowly to reduce the risk of feeling light-headed when taking both medicines.
• Seek urgent help if you have an erection lasting more than four hours, sudden vision or hearing loss, or chest pain during sex.
• Lorazepam itself can sometimes contribute to erectile difficulties; discuss long-term anxiety treatment with your GP.

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