Testosterone Injections vs Gel vs Pellets: What Actually Separates Them

Ask a clinic which testosterone to start on and the answer usually depends on what that clinic is set up to sell. Injections if there is a nurse. Pellets if there is a procedure room. Gel if the whole thing runs by mail. None of that is a clinical argument, and the eight approved routes genuinely are not interchangeable — they differ in how flat your levels sit, who else in your house is at risk, and whether your sperm count survives the year.

What are the actual options, side by side?

Eight routes are approved in the United States. The pharmacokinetic figures below come from the published prescribing information and from a review of testosterone preparations in Translational Andrology and Urology; the adverse-event percentages come from each product’s own label.

Method	Typical schedule	Level pattern	The catch
IM cypionate or enanthate	50–400 mg every 2–4 weeks, or 75–100 mg weekly	Peak about 1,112 ng/dL at day 4–5, falling to about 400 ng/dL by day 14	Mood and libido track the cycle; injection-site pain
SC enanthate auto-injector (Xyosted)	75 mg weekly into the abdomen	Flatter than IM; dose adjusted on a trough drawn 7 days after the shot	Label reports raised hematocrit in 14.0%, hypertension in 12.7%, raised PSA in 12.0%
IM undecanoate (Aveed)	750 mg, again at 4 weeks, then every 10 weeks	Peak about 813 ng/dL by day 7; trough 323–339 ng/dL at week 10	Boxed warning for pulmonary oil microembolism and anaphylaxis; 30 minutes of observation after every dose, under a restricted programme
Transdermal gel (AndroGel, Testim, Fortesta, Vogelxo)	40–100 mg daily depending on the product	In range within 1–2 days, then steady	Boxed warning for transfer to others; no swimming or showering for at least 5 hours
Transdermal patch (Androderm)	2–6 mg nightly, starting at 4 mg	Peak about 765 ng/dL around 8 hours; roughly mimics the natural daily rhythm	Skin irritation in 48% of users
Nasal gel (Natesto)	11 mg per dose (5.5 mg per nostril), three times daily	Peak within 40 minutes; 24-hour average about 421 ng/dL	Three doses a day forever; nosebleed, runny nose, nasal scabbing
Oral undecanoate (Jatenzo and similar)	158–396 mg twice daily, with food	Absorbed through the lymphatics, bypassing first-pass liver metabolism	Ambulatory monitoring showed blood pressure up 4.9/2.5 mm Hg; useless without a fatty meal
Subcutaneous pellets (Testopel)	150–450 mg implanted every 3–6 months	Peak about a month after implant, then sustained for 4–6 months	Minor surgical procedure; extrusion in about 10%; very hard to reverse if you react badly

A buccal tablet held against the gum also exists on paper. It worked — levels held between roughly 580 and 700 ng/dL — but gum irritation affected about 18% of users and it has effectively disappeared from practice.

Which method keeps levels steadiest?

This is the question most men are actually asking when they ask which method is “best”, because the complaint that drives people to switch is rarely a lab value. It is the week-three slump.

Long-interval intramuscular dosing is the worst offender by design. A 200 mg shot every two weeks puts you well above the reference range for several days and near the bottom of it by the time the next one is due. The ester has not failed; it is doing exactly what an oil depot does. Splitting the same monthly total into weekly or twice-weekly doses flattens the curve without changing the drug, which is why weekly dosing has quietly become the default in andrology practice even though the older label language allows the longer gap.

Daily routes — gel, patch, oral, nasal — are steadier across weeks but introduce a within-day peak and trough instead. The patch is the only one that deliberately reproduces the overnight rise and morning peak of natural secretion. Whether that matters clinically has never been demonstrated in a trial with symptom endpoints, and it would be dishonest to claim otherwise.

Pellets give the flattest long curve of all, at the cost of control. If the dose is wrong, you live with it for months.

Which method is riskiest for the people around you?

Only one class of testosterone product carries a boxed warning about somebody other than the patient, and it is the one most often prescribed by mail.

The gel label is blunt: virilization has been reported in children secondarily exposed to testosterone gel. The reported effects in children include enlargement of the genitals, pubic hair, increased erections and libido, aggressive behaviour, and advanced bone age. The handling instructions are not optional garnish — wash hands with soap and water straight after applying, cover the site with clothing once the gel has dried, wash the site thoroughly before any skin-to-skin contact, and do not swim or shower for at least five hours.

If there are small children in the house, or a partner who is pregnant or trying to be, that warning should weigh more heavily than convenience. Injections, pellets and nasal gel carry no equivalent transfer risk.

If you want children, does the method matter?

For seven of the eight routes, no. Exogenous testosterone suppresses the pituitary signals that drive sperm production, and the American Urological Association is unambiguous about the consequence: testosterone therapy should not be prescribed to men currently trying to conceive. That is a strong, Grade A recommendation, not a cautious aside. The guideline instead points to human chorionic gonadotropin, selective estrogen receptor modulators such as clomiphene, aromatase inhibitors, or a combination, for men who need treatment and want to stay fertile.

Nasal gel is the interesting exception. Because it is absorbed and cleared quickly, three times a day, the theory is that the pituitary is never suppressed long enough to shut spermatogenesis down. A single-centre trial tested it.

Natesto, 11 mg three times daily, 6 months	Result
Reached normal testosterone (>300 ng/dL) at 6 months	90.9%
FSH held within the normal range at 6 months	81.8%
LH held within the normal range at 6 months	72.7%
Total motile sperm count stayed above 5 million at 6 months	93.9%
Men enrolled / evaluated at 6 months	60 / 33

Did the FDA really drop the boxed warnings?

Partly, and the half that gets repeated is the flattering half.

On 28 February 2025 the FDA ordered class-wide labelling changes for every testosterone product. It removed the boxed-warning language about increased cardiovascular risk, on the strength of the TRAVERSE trial — 5,198 men at high cardiovascular risk, major cardiac events in 7.0% on testosterone gel against 7.3% on placebo. In the same action it required product-specific blood pressure information for every product with a completed ambulatory monitoring study, and a new blood pressure warning for products that had none. The agency’s own summary is that those studies confirmed an increase in blood pressure across the class. It also kept the limitation of use saying these products are not established for low testosterone caused simply by ageing.

Separately, two products that carried their own boxed warning for raised blood pressure — the Xyosted auto-injector and the oral undecanoate Jatenzo — had those removed during 2025. Blood pressure now sits in Warnings and Precautions on both labels rather than in a box, with the underlying figures unchanged: 3.9/1.5 mm Hg for Xyosted at week 12, 4.9/2.5 mm Hg for Jatenzo at four months.

So which one should you ask for?

The AUA guideline deliberately does not rank them. It makes one procurement point — use commercially manufactured products rather than compounded testosterone where possible — and otherwise leaves the choice to the consultation. That is the correct posture, because the deciding factor is usually about your life rather than your chemistry.

Weekly or twice-weekly injection of generic cypionate or enanthate is the cheapest route and the only one available as a generic, and self-injecting subcutaneously is a smaller ask than most men expect. Gel suits people who will not inject, provided nobody small lives in the house. Nasal is for the man who wants treatment and children in the same year, understanding the evidence behind that is thin. Pellets suit people who genuinely will not remember anything more often than twice a year, and who accept that the dose is then locked in. Oral works if you eat properly twice a day and your blood pressure has room in it.

Whatever the route, the monitoring does not change. Diagnosis needs two separate early-morning total testosterone measurements below 300 ng/dL. Hemoglobin and hematocrit are checked before starting, because polycythemia is the most common reason to stop.

This article is for information only and is not medical advice. It cannot account for your individual circumstances. Talk to a doctor about your own situation, particularly before starting or stopping any prescription medication.