Q:

Can a potion affect others?

When an imbiber is the target of a spell effect because he consumed a potion, is only the imbiber the target of that spell's effect, no matter the spell's usual target entry?
The section on Creating Potions says that

The imbiber of the potion is both the caster and the target. Spells with a range of personal cannot be made into potions.

And the section on Potions it says that

A potion is a magic liquid that produces its effect when imbibed. Potions vary incredibly in appearance. Magic oils are similar to potions, except that oils are applied externally rather than imbibed. A potion or oil can be used only once. It can duplicate the effect of a spell of up to 3rd level that has a casting time of less than 1 minute and targets one or more creatures or objects.

A potion of the 3rd-level Sor/Wiz spell blood scent (created as a 3rd-level spell at caster level 5) has as its Targets

one creature/2 levels, no two of which can be more than 30 ft. apart

Can the imbiber of such a potion affect a another creature in addition to himself with the effect of blood scent? Consider, also, the effects of a potion of moment of greatness (created as a 1st-level spell at caster level 1).

A:

Yes, but only via some finagling.  A potion/oil only has one target normally, and the imbiber may not select additional targets even if he would be allowed to normally as the caster of the spell.  However, a number of spells that can be made into potions affect creatures other than their direct target(s) in some way.  None of the methods of doing this involve any decisions normally made by the caster at the time of casting, as:

Potions are like spells cast upon the imbiber. The character taking the potion doesn't get to make any decisions about the effect—the caster who brewed the potion has already done so.  

A cursory overview of ways spells do this by means of example follows:
Wandering Star Motes: because this spell can acquire new targets after being brought into effect, it can be used to affect other creatures (though the initial target must be the imbiber).
Enlarge Person: This spell's effect changes how the drinker can affect others in some ways, and so affects them indirectly.  This is how most potions work.
Moment of Greatness: This spell is capable of being made into a potion, but also affects those in an area.  The area effect functions as normal, and may affect various creatures other than the imbiber.  
Draconic Reservoir: This spell gives the subject of the spell the ability to make choices about the spells' effects, including the targets of some possible new effects.  These choices may still be able to be made by an imbiber.
Blood Scent: This spell has multiple targets.  While the imbiber cannot make use of this, technically the potion's creator could, though things might go badly if the potion was used in the wrong circumstances.  In order to target multiple creatures, the creator would need to make all the choices normally made when selecting a target at the time of casting when the potion is made.  What those choices are is unclear RAW, but at a minimum includes enough information to uniquely identify who would be affected regardless of when the potion is used. 
The imbiber must certainly still be a target, but it is possible that other targets may be added, as target selection is a choice normally made while casting the spell and the rules do not anywhere expressly forbid multi-target potions.
See also: Volatile Vaporizer

A:

The short answer is no. Potions only effect the person that consumes them. The wording 

" It can duplicate the effect of a spell of up to 3rd level that has a casting time of less than 1 minute and targets one or more creatures or objects." 

is meant to explain what types of spells can be turned into a potion or an oil with the exception that 

"Spells with a range of personal cannot be made into potions".

Potions can only be made from spells that target one or more targets (not target personal) because the brewer, in most cases, is not the imbiber. Therefore in order to create a magic item (potions are magic items) that effects the person using it (the imbiber) the brewer would have to use a spell that can target others. However, the brewer has already chosen the number of targets effected (as stated in the text) by the act of brewing. It's one, the imbiber.
The text follows the natural law of consumption. If you drink a bunch of alcohol would your buddy get drunk from you doing that? No. The same goes for potions. If you drink one no one else is effected but you.

