Medically reviewed by Mary Lucas, MSCIS, MPhil, RN
Written by Our Editorial Team
Last updated 11/3/2021
For centuries, people have turned to aphrodisiacs in an attempt to to boost their sex drive and enhance their sex appeal.
Spanish fly is one such aphrodisiac. Made famous by Bill Cosby in a now-controversial stand-up routine from the 1960s, Spanish fly is a name that’s used to refer to all sorts of tonics, potions and other “love supplements” made from blister beetles.
Spanish’s fly’s reputation isn’t the best. It’s linked to a long list of potential side effects, some of which can be deadly, and there’s only limited scientific evidence that it has much of an effect on your attractiveness or sexual performance.
Despite this, Spanish fly is still well-known and somewhat infamous several decades after it first appeared on the scene.
Below, we’ve explained what Spanish fly is, as well as the claims that are often made about its sexual effects.
We’ve also looked into the science on Spanish fly to see if it’s worth using or if it should be avoided.
Finally, we’ve covered some of the risks of using Spanish fly and shared a few alternatives you may want to consider if you’re aiming to boost your sexual desire and performance.
Spanish fly is an informal term that’s used to refer to two things — a type of green blister beetle and the toxic blistering agent called cantharidin that it produces.
Cantharidin has long been used as a natural aphrodisiac. Several millennia ago, it was used by ancient Egyptians and Romans as a stimulant for orgies, improving sexual relationships and as a tool for committing sexual blackmail.
Today, most supplements marketed as “Spanish fly” contain little or no cantharidin. Instead, they often contain various herbal ingredients that manufacturers claim are capable of boosting sexual performance, stamina and attractiveness.
When it comes to aphrodisiacs and male enhancement pills, most are big on promises but small on actual results.
Spanish fly is similar, but a little different. Like most supplements promoted as aphrodisiacs, the evidence that it works is very slim.
However, unlike most herbal supplements, which typically do nothing, real Spanish fly is actually dangerous when it’s consumed by humans.
In fact, the cantharidin that can be found in authentic Spanish fly is listed by the National Center for Biotechnology Information as an irritant and an acutely toxic substance. It’s even featured in the Hazardous Substances Data Bank.
Put simply, authentic Spanish fly isn’t something that you or your partner want to consume. It’s a hazardous substance, and cases of poisonings aren’t unheard of.
Because there’s no standardized formula for Spanish fly, the risks and side effects that you may experience can vary from one supplement to another.
When it comes to products that contain cantharidin, there are real, serious safety risks that you should be aware of if you’re considering taking this type of supplement.
In some cases, people have died from using products that contain cantharidin.
Side effects associated with cantharidin include:
Blistering. Cantharidin is known to cause skin blisters to develop. You may notice skin blisters, a burning sensation in your skin, itching and changes in pigmentation after you use products containing cantharidin.
Blood in saliva, vomit or urine. Cantharidin is known to cause hematemesis (vomiting of blood) and gross hematuria (blood that’s visible in urine). It can also cause dysuria, or pain while urinating.
Priapism. Cantharidin can cause priapism — a type of painful, long-lasting erection that can damage your penis when left untreated. Priapism is a serious medical emergency that requires urgent attention from a healthcare provider.
Cantharidin poisoning can also cause seizures, burning of the mouth, renal dysfunction, cardiac abnormalities, nausea and dysphagia (difficulty swallowing).
In some cases, the effects of cantharidin can be deadly. In England, two women were killed by a man who gave them coconut ice laced with cantharidin in the hope that it would lead to them having sex with him.
Others in the United States have been rushed to the emergency room after taking cantharidin in the hope of stimulating sexual activity.
Because products labeled “Spanish fly” aren’t regulated by the FDA, there’s no real way to know what’s in them, or how much of each specific ingredient is used.
This creates other safety issues, as many herbal sexual performance boosters have been found to contain unlabeled, potentially dangerous ingredients.
In fact, the FDA maintains a long list of tainted sexual enhancements products that can be viewed online.
Because of the serious safety risks of cantharidin and the unknown safety risks associated with over-the-counter sexual enhancement products, we recommend avoiding sexula enhancement products or aphrodisiacs labeled as containing “Spanish fly.”
While Spanish fly is neither safe nor proven to be effective as an aphrodisiac, there are real options available for treating sexual dysfunction and improving your performance in bed.
Some of these require a prescription, while others are available online and over the counter.
If you sometimes find it difficult to get or maintain an erection, you’ll get better results from real, proven ED medications than from natural remedies like Spanish fly or male enhancement pills sold at the local gas station.
These belong to a class of medications referred to as PDE5 inhibitors. They work by increasing blood flow to your penis, making it easier for you to get and maintain an erection when you feel sexually aroused.
We offer several ED medications online, following a consultation with a healthcare provider who will determine if a prescription is appropriate.
Like ED, premature ejaculation is a common sexual performance issue that can cause serious harm to your confidence and sexual pleasure.
Premature ejaculation is very treatable. If you’re prone to PE, you’ll get the best results by using medication to slow down orgasm and ejaculation. Your options include:
Antidepressants. Some antidepressants, including sertraline (Zoloft®) and paroxetine (Paxil®) are used off-label to treat PE. Research shows that these medications help to slow down ejaculation and improve stamina for men with PE.
Topical PE products. It’s also possible to treat premature ejaculation topically. Products such as our Delay Spray for Men are designed to reduce sensitivity, allowing you to have sex for longer before reaching orgasm.
While medication may provide the fastest effects, you’ll get the best results by combining it with a healthy lifestyle.
Try the following habits and lifestyle changes to improve your physical health and your sexual function:
Keep yourself physically active. Regular exercise can have a huge positive impact on your physical health, sexual performance and erectile function. Try to get 150 minutes or more of cardiovascular exercise per week, as well as a couple of strength workouts.
Maintain a healthy body weight. Research has found that being overweight or obese is linked to a higher risk of experiencing ED. Try to maintain a BMI that’s either in or close to the normal range as possible.
If you smoke, try to quit. Research shows that smoking is linked to an increased risk of developing sexual performance issues, including ED. It’s also a key risk factor for other medical conditions, including potentially fatal ones such as cancer and heart disease. If you smoke, try your hardest to quit. Our guide to quitting shares actionable tactics that you can use to kick the habit for better health and improved sexual function.
Live a healthy, balanced lifestyle. From sleep to diet, a variety of factors can all affect your sexual performance. Our guide to naturally protecting your erections shares tactics that you can use to live a life that prioritizes your sexual health and function.
Spanish fly isn’t just ineffective as an aphrodisiac — it’s also dangerous. By using it yourself to increase your sex drive, you’re putting your health at risk.
By giving it to someone else, you’re risking their health and wellbeing.
There’s also the ethical side of using something like Spanish fly. While aphrodisiacs are fine if they’re used consensually, giving someone a herbal aphrodisiac in an effort to make them feel more attracted to you without their permission is both unsafe and illegal.
Instead of thinking of Spanish fly as a romance-inducing aid, it’s far better to keep it, and other herbal aphrodisiacs, at arm’s length.
Instead, set the mood by enjoying a romantic dinner or a glass of wine with your partner — not only is it more effective, it’s also better for your health.
If you need help with your sexual performance, you can view our range of ED treatments online and connect with a licensed healthcare provider to discuss your needs.
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