Male fertility depends on a balance between hormones, healthy testicles, and good-quality sperm. Some common medications —taken long-term or occasionally—can disrupt this balance. This doesn't mean you have to stop essential treatments, but it is helpful to know which active ingredients can affect fertility and how to proceed if you are trying to conceive.
Analgesics and anti-inflammatories
Non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, naproxen, ketoprofen, or acetylsalicylic acid, used at high doses or for a long time, can alter the hormonal profile and temporarily decrease sperm production.
Opioids (tramadol, codeine, morphine) reduce testosterone with chronic use, contributing to erectile dysfunction and decreased libido. When used briefly, their impact is usually less severe and reversible.
Cardiovascular and antihypertensive medications
Several antihypertensive medications have significant side effects. Beta-blockers (propranolol, atenolol, metoprolol) are associated with erectile dysfunction, which, in practice, makes conception difficult. Alpha-methyldopa can increase prolactin levels and secondarily decrease testosterone. Some calcium channel blockers, such as nifedipine, interfere with sperm activation and motility, an effect that usually resolves upon discontinuation. Spironolactone , due to its antiandrogenic effect, can reduce libido and sperm count.
Urological medications
Within urology itself, there are also medications to consider. Alpha-blockers such as tamsulosin or silodosin, very effective in relieving the urinary symptoms of benign prostatic hyperplasia (BPH ), can cause retrograde ejaculation or "dry orgasm": the semen does not exit the body, and therefore no sperm are available for fertilization. 5-alpha reductase inhibitors (finasteride, dutasteride), used for prostate conditions, can reduce semen concentration and volume during treatment. It usually improves after discontinuing them.
Psychotropic drugs
Antidepressants and SSRIs (fluoxetine, sertraline, paroxetine, citalopram) can cause significantly delayed or absent ejaculation and, in some cases, worsen semen parameters (motility and DNA fragmentation). Among antipsychotics , drugs like risperidone or haloperidol can increase prolactin levels, thereby decreasing testosterone, libido , and spermatogenesis. When these effects occur, it is often possible to adjust the dosage or switch to alternatives with less impact on sexual function, always under the guidance of a psychiatrist.
Antiepileptics
In epilepsy, valproate has been associated with decreases in sperm count and motility, which are generally reversible after discontinuation . Additionally, carbamazepine, phenytoin, oxcarbazepine, or levetiracetam may alter semen or hormone levels depending on the patient.
Antibiotics and antifungals
Most anti-infective medications do not affect fertility, but there are exceptions. Some antibiotics ( aminoglycosides such as gentamicin; tetracyclines such as doxycycline; macrolides such as erythromycin), especially with repeated or prolonged treatment, can be toxic to the testicles and worsen semen quality. Oral ketoconazole —a systemic antifungal—reduces testosterone synthesis and, consequently, sperm production. This does not occur with its topical forms.
Immunomodulators
Systemic corticosteroids ( prednisone, methylprednisolone, dexamethasone) at high and prolonged doses can inhibit the hormonal axis that stimulates the testes. Sulfasalazine , widely used in ulcerative colitis and arthritis, is a classic treatment for reversible male infertility due to oligospermia and poor sperm motility.
Other drugs in this group—methotrexate, cyclophosphamide, cyclosporine, azathioprine, and leflunomide—can affect spermatogenesis. Some, like cyclophosphamide, carry a risk of persistent damage. Therefore, in treatments with potential gonadotoxicity, we often recommend considering semen freezing before starting treatment.
cancer drugs
Cancer treatments are the most likely to compromise fertility. Many chemotherapies (especially alkylating agents such as cyclophosphamide, busulfan, or procarbazine) and pelvic/testicular radiotherapy can lead to temporary or even permanent azoospermia. Whenever possible, the standard practice is to cryopreserve semen before treatment begins.
Hormonal and anabolic drugs
Exogenous testosterone therapy (TRT)—in gels or injections—suppresses the production of LH and FSH. The testicle "shuts down," and azoospermia may occur during treatment, with recovery taking months after discontinuation. Anabolic steroids used for athletic purposes produce the same mechanism, but more intensely: azoospermia and testicular atrophy, with slow and incomplete recovery in some cases. Hormonal therapies for prostate cancer (GnRH analogs, antiandrogens) also cause infertility while administered.
How can you suspect that a medication is affecting your fertility?
Some warning signs include: decreased libido, less firm erections, "dry" orgasms or orgasms with very little semen after starting medication, testicular pain or shrinkage, and, of course, the inability to conceive after 6–12 months of regular attempts without contraception. Keep in mind that sometimes there are no symptoms and the problem is only detected in a semen analysis.
What should you do if you suspect a medication is affecting your fertility?
First: do not stop taking the medication on your own . Discuss it with your doctor , urologist, or andrologist. Often, it's possible to adjust the dose or switch to another option with less reproductive impact.
Requesting a sperm analysis and a hormonal profile (testosterone, FSH, LH, prolactin) helps to objectify the situation and guide decisions.
If you are going to start chemotherapy, pelvic radiotherapy, testosterone, or immunosuppressants with risks, consider cryopreserving semen beforehand.
At the same time, take care of the basics : avoid tobacco and drugs, moderate alcohol consumption, maintain a healthy weight, exercise, and manage stress, which also influence semen quality.
Many side effects are dose-dependent and reversible upon discontinuing or changing the medication, but it's advisable to plan ahead if you're trying to conceive. Discussing this with your medical team in advance allows you to manage your condition safely without ruling out having children.
