Testosterone and Drugs
Of course, alchohol and recreational drugs can lower testosterone, something I
cover in my links on
Alcohol and T,
Beer and T and
Marijuana and T.
However, what few men know is that legitimate, FDA-approved pharmaceuticals can
also significantly lower testosterone as well. Making matters worse, most
doctors do not know about this side effect and, even if they do, will very
rarely give their male patients any forewarning.
It is very common for men over 40 to be on more than one medication and many of
these will negatively alter hormone status, including one's androgens.
Let's go through some of the major classes of drugs that can decrease baseline
CAUTION: Do NOT discontinue any medication without discussing it first
with your doctor. In many cases, dosage can be reduced or an alternative
medication found but this should be discussed with your physician first.
1. Antipsychotics. These are especially hard on testosterone through
a variety of pathways but are notorious for raising prolactin levels. Of
course, prolactin fights testosterone and libido and if it goes too high will
lead to sexual dysfunction in many ways. For more information, see my link on
Testosterone and the Antipsychotics.
2. Arrythmias (Amiodarone). This drug for heart arrthymia has high
iodine content and can interfere with thyroid function. 
3. Lithium. Of course, lithium can be a life saver for
someone with bipolar disorder.  However, this can interfere with
the thyroid and lead to hypothyroisim, which in turn can interfere with
testosterone production. 
4. Diabetic (Sulfonylurea). These drugs sometimes used to treat type II
diabetes can result in hypothyroidism and, therefore, potentially, a drop in
5. Oxycodone (Oxycontin). This pain medication tends to raise
prolactin and in some men may lower testosterone.  It also can have a side
effect of very significantly lowering testosterone in some sensitive men as
6. Opiate Pain Killers (Percocet, Vicodin, Morphine, etc.). These
all will tend to lower testosterone via inhibition of LH (leutinizing hormone),
the molecule released by the pituitary to signal the testes to increase
testosterone production. One review noted that "a large majority of men consuming sustained-action opioids have symptomatic
androgen deficiency which apparently responds to replacement therapy.
Opioid-induced androgen deficiency is frequently overlooked."
7. Dopamine Antagonists (Chlorpromazine, Compazine, etc.). Anything
that interferes with dopamine levels can easily diminish T levels. These
psychotropics are no exceptions.
NOTE: I cover some of the famous "anti-aphrodisiac", libido-reducing
medications at the bottom of my link on Male Libido Supplements.
8. Antihypertensives (Beta Blockers). Several studies have shown
that beta blockers, a very common class of medications for high blood pressure
can lower testosterone. For example one study found that atenolol, metoprolol,
pindolol and propranolol all led to decreased testosterone levels. Propranolol was found the above study to be the worst. 
9. Valium (Diazepam). One theme you may have noticed: almost any
medication that affects the brain and/or brain function significantly tends to
lower testosterone. Valium, the famous tranqualizer, is no exception and appears
to tranqulized the testes as well. 
CAUTION: There are a wide variety of toxins, pesticides, endocrine
disruptors, xenoestrogens, excitotoxins and other chemicals that can be
considered "drugs" even though they are not pharmaceuticals. I give
significant coverage to these on my site at this link on
Nasty Chemicals That Can Lower Testosterone.
10. Anticonvulsants. These drugs commonly used to treat epilepsy lead to an
interesting phenomenon: an increase in total testosterone but a decrease in free testosterone.
 This situation arises from an increase in SHBG. So who wins? The
increased total T or the decreased free? Unfortunately, in the above
study, the loss of free testosterone correlated well with decreased sexual
11. Antifungal (Nizoral or Ketoconazole). Even something as simple as
trying to get rid of a fungal infection can lower T levels appreciably. 
12. Tagamet (Cimitidine). Strange as it may seem, this H2 Agonist
Blocker for stomach issues actually directly lowers testosterone production.
 In fact, one animal study labelled it as an antiandrogen.  Can't be
any more clear that that, eh?
13. Antidepressants (SSRI's). SSRI's are notorious for lowering
libido and leading to sexual dysfunction in both men and women. Depression
itself is notorious for lowering testosterone, something I discuss in my link on
Depression and Testosterone, likely
due to its increase in cortisol levels as a stressor. This makes it
difficult to tease out if SSRI's actually lower testosterone, since it is a side
effect of the very illness these medicaitons are trying to treat. And,
indeed, one study actually found that SSRI's may increase T levels in men. 
However, more recent research showed very much the opposite. Some studies have shown
that most SSRI's significantly affect liver enzymes and thus some postulate that
they slow down the time to clear estrogen (estradiol), i.e. allow for estradiol
to build up.  One report noticed a wide variety of SSRI's that resulted in
lower free T levels as well. 
But the most damning evidence came from studies on Prozac, which shows that, particularly in those who use it longer term, that testosterone levels do tend to drop. See my page on Testosterone and Prozac
for more information.
3) Journal of Pain and Symptom Management, Feb 1994, 9(2):126–131, "Altered
sexual function and decreased testosterone in patients receiving intraspinal
4) Current Opinion in Endocrinology & Diabetes, Jun 2006, 13(3):262-266,
"Opioid-induced androgen deficiency"
6) Systems Biology in Reproductive Medicine, 1979, 3(1):31-35, "Effect of
diazepam on serum testosterone and the ventral prostate gland in male rats"
7) Arch Sex Behav, 1988 Jun, 17(3):241-55, "Beta-blocker effects on sexual
function in normal males"
8) J Neurol Neurosurg Psychiatry, 1983, 46:824-826, "Sex hormones, sexual
activity and plasma anticonvulsant levels in male epileptics"
9) Eur J Clin Pharmacol, 1985, 29(4):489-93, "Effect of a single administration
of ketoconazole on total and physiologically free plasma testosterone and 17
beta-oestradiol levels in healthy male volunteers"
10) Arch Intern Med. 1985;145(5):920-922, "Cimetidine Blocks Testosterone
11) Gastroenterology, 1979, 76(3):504-508, "Cimetidine is an antiandrogen in the
12) Journal of psychosomatic research, 03/2012, 72(3):205-13, "Salivary
testosterone: associations with depression, anxiety disorders, and
antidepressant use in a large cohort study"
13) European Neuropsychopharmacology, Apr 2006, 16(3):178–186, "The effect of
tricyclic antidepressants, selective serotonin reuptake inhibitors (SSRIs) and
newer antidepressant drugs on the activity and level of rat CYP3A"