{"id":1780,"date":"2026-08-23T09:00:00","date_gmt":"2026-08-23T16:00:00","guid":{"rendered":"https:\/\/vistaralabs.ca\/tesamorelin-reconstitution-bacteriostatic-water\/"},"modified":"2026-09-21T17:33:49","modified_gmt":"2026-09-22T00:33:49","slug":"tesamorelin-reconstitution-bacteriostatic-water","status":"publish","type":"post","link":"https:\/\/vistaralabs.ca\/fr\/tesamorelin-reconstitution-bacteriostatic-water\/","title":{"rendered":"How Much Bacteriostatic Water for a Tesamorelin 10 mg Vial?"},"content":{"rendered":"

A 10 mg vial of tesamorelin reconstituted with 2 mL of bacteriostatic water gives a concentration of 5 mg\/mL; with 1 mL it gives 10 mg\/mL. The calculation depends only on the quantity of peptide in the vial and the volume of water added, so the figures below apply to any 10 mg vial.<\/p>\n

There is no single correct volume. Adding more water does not change how much peptide is in the vial. It spreads the same quantity through a larger volume, which changes how many syringe units correspond to a given mass. The tables on this page use 2 mL because it produces round numbers on a U-100 syringe; 1 mL, 3 mL or 5 mL work identically as long as the resulting concentration is written on the vial.<\/p>\n

Concentration by water volume<\/h2>\n

Concentration is peptide mass divided by water volume. A 10 mg vial holds 10 mg whether it receives 1 mL or 5 mL; only the mg\/mL figure moves. The right-hand column converts each concentration into the number of U-100 units that contain 1 mg.<\/p>\n\n\n\n\n\n\n\n\n
Vial<\/th>\nBacteriostatic water added<\/th>\nConcentration<\/th>\nUnits containing 1 mg<\/th>\n<\/tr>\n<\/thead>\n
10 mg tesamorelin<\/td>\n1 mL<\/td>\n10 mg\/mL<\/td>\n10 units<\/td>\n<\/tr>\n
10 mg<\/td>\n2 mL<\/td>\n5 mg\/mL<\/td>\n20 units<\/td>\n<\/tr>\n
10 mg<\/td>\n3 mL<\/td>\n3.33 mg\/mL<\/td>\n30 units<\/td>\n<\/tr>\n
10 mg<\/td>\n5 mL<\/td>\n2 mg\/mL<\/td>\n50 units<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Before choosing a larger volume, check that the peptide vial has headspace for it. A 10 mL vial of bacteriostatic water reconstitutes five 10 mg vials at 2 mL each.<\/p>\n

Reading the concentration on a U-100 syringe<\/h2>\n

A U-100 insulin syringe is graduated in units, and 100 units equal 1 mL. Units are therefore millilitres multiplied by 100: 0.1 mL is 10 units and 0.25 mL is 25 units. A 0.5 mL syringe carries 50 units and a 0.3 mL syringe carries 30 units on the same scale, with finer markings that make small volumes easier to read.<\/p>\n

To find the volume that contains a given mass, divide the mass by the concentration. At 5 mg\/mL (a 10 mg vial with 2 mL of water), the volume that contains 1 mg is 1 divided by 5, which is 0.2 mL, or 20 units. The table below runs the same calculation for four arbitrary amounts. They illustrate the arithmetic and nothing else.<\/p>\n\n\n\n\n\n\n\n\n
Mass (illustrative)<\/th>\nVolume at 5 mg\/mL<\/th>\nU-100 units<\/th>\n<\/tr>\n<\/thead>\n
0.25 mg<\/td>\n0.05 mL<\/td>\n5 units<\/td>\n<\/tr>\n
0.5 mg<\/td>\n0.1 mL<\/td>\n10 units<\/td>\n<\/tr>\n
1 mg<\/td>\n0.2 mL<\/td>\n20 units<\/td>\n<\/tr>\n
2 mg<\/td>\n0.4 mL<\/td>\n40 units<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

At 10 mg\/mL, which the same vial gives with 1 mL of water, every volume in the table halves: a 1 mg draw measures 10 units and a 0.5 mg draw measures 5 units. Volumes below about 0.1 mL are hard to read accurately on a 1 mL syringe. Either move to a 0.3 mL or 0.5 mL syringe, or reconstitute with more water so that the same mass occupies a larger, more legible volume.<\/p>\n

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Tesamorelin is supplied by Vistara Labs as a lyophilised material for research use. The quantities on this page illustrate the arithmetic of dilution and measurement only.<\/p>\n<\/div>\n

The tesamorelin vial<\/h2>\n

Tesamorelin is a 44-amino-acid synthetic analogue of growth-hormone-releasing hormone. Vistara Labs supplies it as a 10 mg lyophilised vial; the mass on the label is the peptide in the vial, and the tables above treat it as one quantity. Certificates of analysis are published on the Lab Results<\/a> page. The same 10 mg arithmetic covers CJC-1295 + Ipamorelin<\/a>, the other GHRH-axis vial in the catalogue.<\/p>\n

What sets tesamorelin apart from natural GHRH<\/h2>\n

Natural growth-hormone-releasing hormone is broken down within minutes, largely by the enzyme DPP-4, which clips the first two amino acids off the front of the molecule. Tesamorelin is the full 44-amino-acid GHRH sequence with one change: a trans-3-hexenoyl group attached to that front end. The modification shields it from DPP-4, which is why it lasts long enough to study. Being the full-length sequence, tesamorelin is also a larger molecule than sermorelin, the 29-amino-acid GHRH fragment. At about 5,100 daltons it is one of the heavier single peptides on this site, so a 10 mg vial holds fewer molecules than 10 mg of a short peptide; the mass-based tables above apply unchanged.<\/p>\n

Tesamorelin is also an approved medicine, sold as Egrifta since 2010 in the United States for excess abdominal fat in HIV-associated lipodystrophy, and that product is supplied under its own prescribing information. The research vial here is a separate laboratory material. The molecule is explained in tesamorelin: one small change to a natural hormone<\/a>.<\/p>\n

Reconstitution technique<\/h2>\n

Let the vial reach room temperature, swab both stoppers, and run the measured water slowly down the inside wall of the vial rather than onto the powder. Swirl or tilt gently until the cake dissolves, never shake, and give any remaining powder a few minutes to settle into solution. Label the vial with the date and the concentration, then keep it refrigerated at 2 to 8 °C and protected from light. The full method, with the reason behind each step, is in how to reconstitute peptides with bacteriostatic water<\/a>.<\/p>\n

Why the solution should look clear<\/h2>\n

Properly reconstituted tesamorelin forms a clear, colourless solution. Cloudiness, strands or a gel that will not disperse usually mean the water went in too fast or the vial was shaken; haze that appears later points to warm or bright storage. The causes are covered in why peptides gel or go cloudy<\/a>.<\/p>\n

Bacteriostatic water, not sterile water<\/h2>\n

Bacteriostatic water is sterile water with 0.9% benzyl alcohol, a preservative that allows a refrigerated vial to be accessed more than once; plain sterile water is intended for single access. The difference is explained in bacteriostatic water explained<\/a>.<\/p>\n

Frequently asked questions<\/h2>\n

How much bacteriostatic water do I add to a 10 mg vial of tesamorelin?<\/h3>\n

There is no single correct volume. With 2 mL of bacteriostatic water a 10 mg vial of tesamorelin gives 5 mg\/mL; with 1 mL it gives 10 mg\/mL. Adding more water does not change the quantity in the vial, it spreads it through a larger volume, so write the concentration you chose on the vial.<\/p>\n

How many 10 mg vials does a 10 mL vial of bacteriostatic water cover?<\/h3>\n

A 10 mL vial of bacteriostatic water reconstitutes five 10 mg vials at 2 mL each. Check that the peptide vial has headspace for the volume before choosing a larger one.<\/p>\n

How many units on a U-100 syringe contain 1 mg at 5 mg\/mL?<\/h3>\n

At 5 mg\/mL (a 10 mg vial with 2 mL of water), the volume that contains 1 mg is 1 divided by 5, which is 0.2 mL, or 20 units. Units are millilitres multiplied by 100, so 0.1 mL is 10 units. The amounts on this page illustrate the arithmetic only.<\/p>\n

What should reconstituted tesamorelin look like?<\/h3>\n

Properly reconstituted tesamorelin forms a clear, colourless solution. Cloudiness, strands or a gel that will not disperse usually mean the water went in too fast or the vial was shaken; haze that appears later points to warm or bright storage. More on the causes in why peptides gel or go cloudy<\/a>.<\/p>\n

Can I use sterile water instead of bacteriostatic water?<\/h3>\n

Only for a vial that will be accessed once. Bacteriostatic water is sterile water with 0.9% benzyl alcohol, a preservative that allows a refrigerated vial to be accessed more than once; plain sterile water is intended for single access. Details in bacteriostatic water explained<\/a>.<\/p>\n

How should a reconstituted tesamorelin vial be stored?<\/h3>\n

Refrigerated at 2 to 8 \u00b0C, protected from light and labelled with the date and the concentration. Unopened lyophilised vials are kept cold and dark until they are needed. The full storage guide is how to store research peptides<\/a>.<\/p>\n

Work it out for a different vial or concentration<\/h2>\n

Our peptide calculator<\/a> opens pre-set for a 10 mg vial with 2 mL of water and marks the 1 mg draw of 20 units on a syringe diagram. Change the vial size, water volume, mass or syringe and it recalculates.<\/p>\n

Products: Tesamorelin 10 mg<\/a> and bacteriostatic water 10 mL<\/a>.<\/p>\n

Related reading.<\/strong> Tesamorelin and visceral fat: the trial record<\/a>, CJC-1295 + Ipamorelin vs tesamorelin<\/a> and the Canadian buying guide<\/a>.<\/p>\n