There are hundreds of medicines, some commonly used drugs, that can affect a man’s sex life and sexual performance. Many of these drugs are necessary for treatment of depression and hypertension and shouldn’t be stopped. This blog will discuss the causes of medications and deterioration of sex drive and sexual performance.
How can medicines affect sexual function?
The mechanism of sexual function involves a complex coordination of hormones, chemical messengers in the brain (neurotransmitters such as dopamine and serotonin) and the sexual organs. In general:
- dopamine increases sexual function
- serotonin inhibits sexual function
- the hormone testosterone is important, as are the blood vessels supplying the penis are also involved in producing an erection.
A medicine can therefore affect sexual function in several ways.
Libido or sex drive
Sex drive is influenced by reproductive hormones, particularly testosterone, which is required for sexual arousal.
Medicines that reduce the testosterone level or block its effects are likely to reduce sex drive.
Libido is also affected by your general emotional and physical health. Medicines that affect any of these aspects, even indirectly by causing drowsiness, lethargy, weight gain or confusion, have the potential to reduce your sex drive.
An erection is the result of coordination between nerves, hormones, blood vessels and psychological factors. This means there are many areas where things can go wrong.
Medicines that have a physical effect on the blood vessels in the penis, those drugs that act on the brain or interfere with hormone levels (particularly testosterone) or affect the transmission of nerve messages, can all cause impotence.
Ejaculation is a complex reflex process that involves the activation of alpha receptors in the prostate gland and seminal vesicles.
Medicines that block alpha-receptors can interfere with ejaculation.
During ejaculation, increased alpha-receptor activation closes the bladder neck, facilitating the normal flow of semen out of the penis.
If this mechanism is disrupted, it results in retrograde ejaculation, with semen flowing along the path of least resistance from the urethra up into the bladder.
Various chemicals in the brain are also involved in orgasm and ejaculation, and medicines that affect these chemicals can also cause ejaculatory disturbances.
The most widely prescribed centrally acting agents that affect ejaculation are selective serotonin re-uptake inhibitor (SSRI) antidepressants.
Antidepressants are the medicines most frequently implicated in causing sexual dysfunction. This is because they work by altering levels of chemicals in the brain. In particular, SSRIs increase serotonin levels, which inhibits sexual function.
Blood pressure lowering (antihypertensive) medicines are also implicated, although the mechanism by which they cause sexual problems will vary from medicine to medicine.
The table of medicines below lists the sexual side effects that some people have reported during their use.
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Antidepressants | Main use | Possible effect on sexual function |
MAOI antidepressants (eg moclobemide, phenelzine) | Depression | Decreased sex drive, impotence, delayed orgasm, ejaculatory disturbances |
SSRI antidepressants (eg fluoxetine) | Depression | Decreased sex drive, impotence, delayed or absent orgasm, ejaculatory disturbances |
Tricyclic antidepressants (eg amitryptiline) | Depression | Decreased sex drive, impotence, delayed or absent orgasm, ejaculatory disturbances |
Antiepileptics | Main use | Possible effect on sexual function |
Carbamazepine | Epilepsy | Impotence |
Antihypertensives | Main use | Possible effect on sexual function |
ACE inhibitors (eg enalapril, lisinopril) | High blood pressure, heart failure | Impotence |
Alpha-blockers (eg prazosin, doxazosin) | High blood pressure, enlarged prostate | Impotence, ejaculatory disturbances |
Beta-blockers (eg atenolol, propranolol and including timolol eye drops) | High blood pressure, angina, glaucoma | Impotence |
Calcium channel blockers (eg verapamil, nifedipine) | High blood pressure, angina | Impotence |
Clonidine | High blood pressure | Impotence, decreased sex drive, delayed or failure of ejaculation |
Methyldopa | High blood pressure | Impotence, decreased sex drive, ejaculatory failure |
Thiazide diuretics (eg bendroflumethiazide) | High blood pressure | Impotence |
Antipsychotics | Main use | Possible effect on sexual function |
Phenothiazines (eg chlorpromazine, thioridazine) | Psychotic illness | Ejaculatory disturbances, decreased sex drive, impotence |
Risperidone | Psychotic illness | Impotence, ejaculatory disturbances |
Cholesterol lowering medicines | Main use | Possible effect on sexual function |
Fibrates (eg clofibrate, gemfibrozil) | High cholesterol | Impotence |
Statins (eg simvastatin) | High cholesterol | Impotence |
Other | Main use | Possible effect on sexual function |
Benzodiazepines | Anxiety and insomnia | Decreased sex drive |
Cimetidine | Peptic ulcers, acid reflux disease | Decreased sex drive, impotence |
Cyproterone acetate | Prostate cancer | Decreased libido, impotence, reduced volume of ejaculation |
Disulfiram | Alcohol withdrawal | Decreased sex drive |
Finasteride | Enlarged prostate | Impotence, decreased sex drive, ejaculation disorders, reduced volume of ejaculation |
Metoclopramide | Nausea and vomiting | Decreased sex drive, impotence |
Omeprazole | Peptic ulcers, acid reflux disease | Impotence |
Opioid painkillers (eg morphine) | Severe pain | Decreased sex drive, impotence |
Prochlorperazine | Nausea and vomiting | Impotence |
Propantheline | Gut spasm | Impotence |
Spironolactone | Heart failure, fluid retention | Impotence, decreased sex drive |
Bottom Line: This blog makes the connection between medications and sexual performance. The next blog will discuss how to
approach your physician and what options are available for men who have sexual side effects from medications.