Short answer: Testosterone nasal gel has a half-life of about 10 to 100 minutes. Levels peak about 40 minutes after a dose. People vary, so treat these as estimates.
Natesto (Acerus) is testosterone in a gel pumped into the nose, where it is absorbed through the lining. It is used three times a day for men with low testosterone from testicular or pituitary causes, and has a much shorter action than shots or skin gels.
Also known as: Natesto, nasal testosterone.
One Natesto pump delivers 5.5 mg of testosterone. A dose is one pump in each nostril (11 mg), three times a day, 6 to 8 hours apart, for 33 mg a day. A new pump is primed by pressing it 10 times into a sink.
The Natesto label approves it as testosterone replacement in adult men with low or absent testosterone from primary hypogonadism (testicular failure) or hypogonadotropic hypogonadism (a pituitary or hypothalamus cause). The label says safety and efficacy have not been established for "age-related hypogonadism" or under 18. Label dosing is 11 mg (one pump per nostril) three times a day, morning, afternoon and evening. The nose is blown first, and not blown or sniffed for 1 hour after. Testosterone is checked from one month in; if consistently above 1,050 ng/dL Natesto is stopped, and if consistently below 300 ng/dL another treatment is considered.
The label has no boxed warning. It is not recommended with a history of nasal disorders or nasal or sinus surgery, a recent nasal fracture, or sinus disease. Warnings cover nasal side effects, high red blood cells (hematocrit checked at start, 3 to 6 months and yearly), blood clots, prostate effects, blood pressure increases, abuse, lower sperm counts, swelling, breast growth and sleep apnea. In the 90-day study (78 men, no placebo), PSA increase was 5.1% and runny nose, nosebleed and nasal discomfort 3.8% each. Full numbers are on the Natesto side effects, Natesto dosing schedule, missed Natesto dose and Natesto storage pages, and Natesto vs AndroGel compares it with skin gel.
The Natesto label says testosterone peaks within about 40 minutes of a dose and has a half-life of 10 to 100 minutes. That short action is why the label doses it three times a day, 6 to 8 hours apart.
Numbers shown are taken from the source above. Half-life varies from person to person.
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